UltiDev LLC (http://www.ultidev.com) made a real, free ASP.NET web
server based on Cassini. UltiDev Cassini can run on platforms where IIS
is not an option, like Windows XP Home, and uses the original Cassini
code for requests handling, but added following features:
- Cassini Explorer - an ASP.NET application management UI;
- A simple .NET API for programmatic application registraion with
Cassini;
- A self-installing merge module with Cassini Web Server to include
with your distributable web applications;
- UltiDev Cassini runs as a windows service, can host multiple
applications at the same time, and can easily be used with VisualStudio
to debug ASP.NET applications;
- UltiDev Cassini comes in two flavors: 2.0 for ASP.NET 2.0 and 1.1
applications, and 1.1 - for ASP.NET 1.1 applications;
- Supports all the ASP.NET features and can run applications as complex
as DotNetNuke;
- It's absolutely free to download and redistribute with your ASP.NET
applications.

Additional Information:
UltiDev Cassini product description:
http://www.ultidev.com/products/Cassini/
Download UltiDev Cassini Web Server: http://www.ultidev.com/download/
UltiDev Cassini FAQ:
http://www.ultidev.com/Forums/default.aspx?g=topics&f=2
Cassini Debug and Distribution Walkthrough:
http://www.ultidev.com/Products/Cass...niDevGuide.htm