Free Server-side Scripting

Server-side scripts are scripts which run on your Webserver. Most Webspace providers support PHP and Perl.
PHP
Easy yet powerful scripting language for creating WWW scripts available for a very large number of platforms. Supports object-oriented programming. Most Internet providers offer PHP as part of their Webhosting packages.See also below.
Perl
Perl is an extremely powerful and widely supported scripting language, mostly used for creating WWW scripts. Supports object-oriented programming. Rather difficult to use for Perl-beginners. Most Internet providers offer Perl as part of their Webhosting packages.
Zope
A free, Open Source(tm) web application platform used for building high-performance, dynamic web sites.
Python
Python is an interpreted, interactive, object-oriented programming language. It is often compared to Tcl, Perl, Scheme or Java.Python combines remarkable power with very clear syntax. It has modules, classes, exceptions, very high level dynamic data types, and dynamic typing. There are interfaces to many system calls and libraries, as well as to various windowing systems (X11, Motif, Tk, Mac, MFC). New built-in modules are easily written in C or C++. The Python implementation is portable: it runs on many brands of UNIX, on Windows, DOS, OS/2, Mac, Amiga, etc. Python is copyrighted but freely usable and distributable, even for commercial use.
Rebol
Free for non-commercial use. Very easy to use and elegant interpreted language useful for creating Web applications. Rebol supports object oriented programming. It includes 14 Internet protocols, like HTTP, FTP, CGI, SMTP, POP, etc.Rebol runs on more than 20 platforms, which means that the scripts listed on the Rebol site will not only be able to run on Windows but will also run on Solaris, Irix, NetBSD, OpenBSD, BSDi, BeOS, Mac, AIX, HPUX, Amiga, Linux, etc.Rebol/Command, (which is not free) provides additional features:Direct database access to: Oracle 8 (Windows, Solaris Sparc, and Linux libc6 systems) MySQL 3, ODBC access (from Windows) to: Access, Excel, MS SQL Server, Oracle, MySQL.Also: FastCGI, SSL, TLS, HTTPS, SSLv2, SSLv3 and TLSv1, DES, 3DES, ARCFOUR, RSA keys and DSA/DH keys, Blowfish, Rijndael/AES.
Java Servlets
Java 'applets' which are executed on the server, resulting in a dynamic page that can be viewed in the client Webbrowser.
ASP2PHP
Free tool to convert Microsoft ASP Web scripts to PHP scripts.

Tutorials, Guides, Tips & Resources

Tutorials, Guides, Tips & Resources
Copyscape
Free online search engine which can find illegal copies (plagiarism) of your Web-pages.
Free OnlineWebmasters Resources
Free scripts, search engine tools, HTML validation tools, meta tag generator, CSS validation, etc.
Homepage MadeEasy
The Web Site Owners' Companion: Free Guide, Tools, Tips, Help, Tutorial, Images ...
PageTutor.com
HTML and Javascript tutorials.
SitePoint
Articles, tutorials and backgrounds related to Web development.

Internet Diagnostics Utilities

Internet Diagnostics Utilities
CentralOps.net
Free online network utilities, such as ping, nslookup, traceroute.
DNS Tools
Resolve/reverse lookup, whois (domain name), whois (ip owner), check port, ping.
Network-Tools.com
Ping, trace, whois, spam blacklist check, etc.
Online Nettools
Reverse lookup (host), nslookup, whois IP, whois Domain, bandwidth meter, check port, ping host, traceroute to host, port scanner, mail relaying.
Online network tools
Show me my IP address, IP calculator, ping online, traceroute online, IP geolocation, convert IP to domain name, get MX record, DNS dig, Whois, open relay test, speed test, service name -> port TCP/UDP, port TCP/UDP -> service name, online cron generator.
ping.eu
Ping, traceroute, DNS lookup, whois, port check, reverse lookup, proxy checker, mail relaying, bandwidth meter.
T1 Shopper
Whois, ping, port scanner, nslookup, traceroute

HTML/link validation

HTML/link validation
The free online services in this section allow you to check your Web pages for errors, compliance with HTML standards and compatibility with the most common Web browsers.
CSE HTMLValidator Lite
Free online HTML validator with a number of additional features.
CSSCheck
Free online service for checking style sheets.
HTML Validation Online
Enter the URL of the page, and this service validates the correctness of the HTML inside the Web page.
LinkScan
Free online link-checker (including HTML syntax validation).
W3C CSSValidation Service
A free online service for checking Cascading Style Sheets (CSS) in (X)HTML documents or standalone for conformance to W3C recommendations.
W3C Link Checker
Checks whether your Web page has any broken links.
W3C MarkupValidation Service
Checks Web documents for errors and conformance to W3C Recommendations and other standards. Free online service.
Web Page Purifier
Free online service which checks your Web pages for compliance with HTML standards
Xenu's Link Sleuth
Free utility for Windows which finds broken links on web sites.

URL forwarding

URL forwarding
1try.com
Free web-forwarding. You get an URL like "http://www.1try.com/joe".
Biz.Vi Networks
Free web-redirection service. You get a Website address similar to "yourname.biz.vi".
CJB.net
Free URL-redirection service. You get an URL like "yourname.cjb.net".
EU.org
The goal of EU.org is to provide free EU.org subdomain registration to users or non-profit organizations.
Your.1dr.biz
Free URL redirection and directory, which offers free subdomains like "YOU.1dr.biz" with no ads, and free instant listing in "The First Adaptive Directory".

Free Background-creation programs

Free Background-creation programs
sTile
A graphics program to create seamless 'tiles' which can be used e.g. as background images for web pages. It has many filters and effects

Free image converters

Free image converters
36-Image converter
Converts from/to bmp, gif, jpeg, icon, tiff, pdf, pii, etc. Other features: resize, merge, re-color, filters for eg. grayscale, roman effect, lighten, darken, etc.
Formati
(Batch) graphics file converter; load formats: bmp, gif, jpg, png, wmf, emf, ico, icl, bmp, tga, tif, pcx, pcd, psd, psp, ppm, sgi, cut and eps; save formats: bmp, gif, jpg, png, tif, tga, ico and icl. Features: 34 effects including buttonize and seamless; Shape and Text tool; Twain scan; GIF and JPG optimizer; overlays; screen capture; smart resize; turn; PNG alpha support (mask based variable transparency); adjustable blending of two images; scriptable drawing wizards (HTML+javascript); create and edit (multi-image) icons and icon libraries;
Fotosizer
Freeware batch image resizer with many features such as: flip, rotate, convert to black and white; supported image formats: JPEG, PNG, BMP, TGA, GIF.
Omniformat.com
Free document conversion utility which allows dynamic conversion and image manipulation of over 75 file formats including HTML, DOC, XLS, WPD, PDF, JPG, GIF, TIF, PNG, PCX, PPT, PS, TXT, Photo CD, FAX and MPEG. Also: optical character recognition.
Photoscape
Free image viewer, converter and editor for Windows.
PIXresizer
Freeware image resizing program for Windows. It can also convert between image formats (JPEG, GIF, BMP, PNG and TIFF), rotate images, convert to grayscale and resize multiple images in batch mode

Free image optimizers

Free image optimizers
Dynamic Drive
Free online image optimizer. Reduce the size of your (animated) GIF, JPG, and PNG images. You can also convert from one image type to another.
GIF/JPEG Cruncher
Free service. Compresses GIF/JPEG files from the Web or from your harddisk. You can compress as many images as you like.

Free and non-free HTML editors

Free and non-free HTML editors
1st Page 2000
Free HTML editor for Windows.
Arachnophilia
Freeware HTML editor. Since it has been created in Java it runs on almost any operating system.
Cobalt Web Builder
Cobalt Web Builder is ANOTHER WAY of authoring HTML documents than WYSIWYG editors or simple text editors. The software uses TEMPLATE and SUBSTITUTION, which helps editing web document EASY and QUICK, especially when using CSS and JAVASCRIPT.
KompoZer
Free HTML editor for MAC, Linux and Windows.
NVU
Free Web authoring system for Linux (also Windows and MAC) in the tradition of DreamWeaver and FrontPage.
TreePad
With only a few mouse-clicks, TreePad can generate a complete Web site, including HTML pages, dynamic Javascript tree pane, images (GIF, JPEG, PNG), hyperlinks and index page. Please click here for an example.Websites generated with a special TreePad edition called TreePad X Enterprise also include a PHP search engine.Shareware for Windows.
Trellian WebPage
Free WYSIWYG html editor for Windows.
WebPlus
Free HTML Editor for Windows created by Serif Software.

Free DNS Services

Free DNS Services
ZoneEdit
Free static and dynamic DNS services for your top level domains. The dynamic DNS service allowing a regular PC (connected to the Internet by cable modem, dsl, and dial up) to host a web site.
dnsExit.com
Free static and dynamic DNS service for your top-level domain. Run your own website, email server, ftp server at home even if it has a dynamic IP address. Also other free DNS services.
FreeDNS
Free DNS Hosting, Dynamic DNS Hosting, Static DNS Hosting, subdomain and domain hosting. Please note that a requirement this free DNS hosting service seems to have is that you are always sharing your domain with others. In other words: others can create subdomains of your domains at will. You have a possibility to block these subdomains, but ONLY after they have been in effect for a while.

Free Webmaster utilities

Free Webmaster utilities
AlertPing
Using AlertPing you can create a list of servers/sites which will be periodically contacted through the standard Ping protocol. This way you can easily detect when a server has gone offline.

Free Website Scripts

Free Website Scripts
Maian Script World
14 free PHP scripts for download, including a shopping card script, calendar, guestbook, etc.
The PHP Resource Index
Thousands of free PHP scripts, such as counters, bulletin boards, calendars, guestbooks, games, file management.
Dynamic Drive
Free Javascripts and DHTML code.
Free JavaScripts
Free Java scripts: user-interface elements, visual and sound effects, forms and validation, etc. etc.
Free Java Applets
Hundreds of freeware Java applets.