Sinatra, and web enabling existing .NET codebases

Aaron Quint gave a very interesting talk at GoGaRuCo:

About using sinatra to quickly and easily REST-enable libraries.
I think this might be a very good fit where we’d like to web/REST enable
our existing .NET codebase assets.

It looks like RESTClient is not quite ready to run from IronRuby (at
least from my tests), but personally, I think this looks quite
compelling as a IronRuby use case.

There are other alternatives for giving a REST interface to our .NET
libs - REST service through WCF, or OpenRasta:
http://trac.caffeine-it.com/openrasta

But I think Sinatra/RESTClient may be faster/easier/less configuration
than the more statically-oriented existing solutions.

Thoughts? Anyone already working on something like this? and if so,
could you provide any insight into the best way to expose library
functionality in this fashion?