Whilst listening to the latest .Net Rocks! podcast, I stumbled across HornGet, which is a site that provides pre-compiled binaries for well known open source projects such as NHibernate, RhinoMocks, etc.
I posted a while back about the problems I had finding a build of NHibernate which works with both FluentNHibernate and Linq2NHibernate, only if I knew about HornGet back then!
There are about 30 odd projects hosted on there for now, separated into a number of categories such as ORM, Logger, etc.