B. Mann Consulting

An interesting site that allows users to post questions and feature requests about a variety of open source technologies. Solution providers in the form of independent consults as well as companies bid on answering the questions or developing features.

Users can band together to fund a feature request, although the lead requester has control over who gets chosen, as well as when the feature is deemed "complete".

Developed by a company in Germany. Similar to ExpertsExchange, but extended to include funding for feature requests.