My friend and I just started a site to help do this: http://leaklist.org/

It's super early, but we've already gotten 500 users who are looking to beta test software and we've already started sending out codes.

Our goal is to make it the best platform for developers to get their first 100 users and the best place for users to get early & free access to awesome apps.

If you're interested please sign up either as a user or a developer—we're sending out stuff weekly!