I would like to contribute anonymously to projects on github. Not to cause mischief, more in the spirit of anonymous donations.
The tool of choice for being anonymo
Configure git proxy server Getting git to work with a proxy server
or if this doesn't work with the TOR network, then simply run your git command in a virtual machine where the host machine is using the TOR network to connect to the outside world
I assume this will obfuscate the origin of your commit, but the anonymous email part may still be difficult.
Anonymous email providers come and go, but as of 2015 Lelantos is currently a TOR hidden service that offers clearnet email addresses. Payable in Bitcoin but you can anonymize all bitcoin transactions using http://www.xmr.to which lets you pay bitcoin receipts using the more private Monero network.
Why not simply do a pseudonymous email that you also create while in TOR, never access it from outside of TOR, and use that for github compliance