Here's something similar for CompSci: http://paperswelove.org/

They had a presentatino on the Paxos paper about a month ago: http://www.meetup.com/Papers-We-Love-London/events/225736762...

Fermat's Library is not only for math, it has a few CS papers already, for instance http://fermatslibrary.com/s/bitcoin. If there is a particular paper you would like to be annotated, you can suggest it and maybe you'll get lucky :)