Recently I was working on a WCF Service and wanted to serve it up with extensionless URLs. I downloaded and installed ISAPI Rewrite (Lite version) but struggled to come up with the correct regex expression to get it working.
I found many good blog postings and clues from Scott Gu, Scott Hanselman, and Jeff Atwood, and a thread on Stack Overflow, but none of these answered this specific question. As Scott Hanselman noted, URL rewriting can seem like "freaking voodoo".
So I moseyed on over to the Helicon Tech support forum and [more] asked the question. Anton (who I assume is one of the good folks at Helicon Tech) swiftly and correctly answered the question with the following example:
RewriteRule ^MyProject/MyService/products(.*)?$ MyProject/MyService.svc/products$1 [NC,L]
You can follow the complete thread here.
I hope this helps!