the best way to protect our open source projects is to make them closed source! Finally, no one can misuse our source code, fork it or clean-room it. because no one can see it at all. problem solved!

It's not easy to land on a comet or asteroid. The gravity's quite weak, and not regular either. Especially as you don't know the composition or internal structure.

Europe will try it with its Rosetta spacecraft. It will arrive in the year 2014.
http://www.esa.int/SPECIALS/Rosetta/SEMYMF374OD_0. html