General:
 * CobraScgi
 * ManosFramework
 * MonoRail
 * SharpWebServer
 * KayakWebServer
 * NancyWebFramework
 * [http://www.codeplex.com/AntiXSS AntiXSS]

Testing with Cobra and browser libraries:

 * [http://watin.org/ WatiN]
 * [http://aspnet.codeplex.com/releases/view/35501 Lightweight Test Automation Framework]

Testing with recorder tools embedded in GUI browsers:

 * [http://www.getwindmill.com/ Windmill]
 * [http://seleniumhq.org/ Selenium]

Testing with command line and/or Python tools:

 * [http://pypi.python.org/pypi/zope.testbrowser zope.testbrowser]
 * [http://twill.idyll.org/ twill]
 * [http://wwwsearch.sourceforge.net/mechanize/ mechanize]

Search help:

 * Web apps
 * Web development
 * Developing web applications

See also: RelatedProjects, DotNetProjects, LibraryTopics