contribution agreements for open source projects

[Jeffrey O'Neill]

Quite a few open-source projects are now requiring that contributors
sign agreements to give ownership or other rights in their
contributions to the project.  One prominent example is Sun's
Contributor Agreement
(http://www.sun.com/software/opensource/sca.pdf).

Can anyone recommend a website that compares the contribution
agreements used by different projects?  I'd like to use one for my
project, but I'd like to consider the options so I can make an
informed choice.

Regards,
Jeff