If you are doing REST webservices in .Net, you may have tried WCF to do this. This can be a bit tricky to setup and get working. Once it is working, it works well, but getting it going can be fun. I was working on a new project last night where I needed some REST services and I had thought about doing it Java or Python to get a quick version up and running so I could test my client, but I really wanted to do it in WCF so I spent a little time searching and came across the WCF REST Starter Kit. This has to be the coolest out of band project I have seen since the ASP.Net Ajax toolkit. If you are doing REST, it is the best/easiest way to get started. It creates a clean web application with a REST service that just works! I say again, It Just Works!
Once I got the REST service working, I needed to hook in some basic http authentication and it didn't take me long to come to Pablo Cibraro's blog. He has a series of posts on how to setup http auth with ASP.Net that authenticates against a custom (non-AD) membership provider. Very cool stuff. Using his posts, I was able to get the basic auth setup very quickly.
If you are planning to do REST with WCF, here are some good resources to help get you going:
WCF REST Starter Kit
Pablo Cibraro's Blog, custom authentication post
Stephen Forte's Blog
Another awesome resource is Dan Rigsby's blog. He has a lot of good WCF stuff there.