Mashery made headlines last week at Web 2.0, not by presenting but by being present.
Mashery launches with two versions of it's service, "free" and "pro". The free version offers a place online for people to find a company's API, along with documentation and peer support. Also cool, this version includes an integrated forum, wiki, and blog (and you only need one login). The pro account, which typically runs around $1000/month, includes extensive metrics (such as precisely who is using the API and how much), issuing of developer keys, security features and server load protection. You can, however, sign up developers for your community with the free version.
I think this service has so very much potential in aiding companies in being successful, in fact, if it had been around in 2000 I bet there would be fewer professionals returning to the Midwest waning "I used to be in that there Internet." So, wood wittlers of Wichita, dust off your IP and sign up for Mashery.