Oceania Online isn't quite beta yet (ETA is June), but the forum admin stated that it is going to work with bitcoin in game.  According to the demo videos, you can set up vendor stalls to sell items for real money which you can withdraw from the game.  There is also in game content you can get with real money, like personal islands.

You can pre-order the beta now.  While bitcoin wasn't listed as an option to pay for the pre-order, I emailed the guy and he let me pay with bitcoin.  Also, the game will run on Linux, as well as other operating systems.

http://oceania-online.com/

I put a screenshot of the post on their forum here.

https://mega.co.nz/#!gt5ESA4I!EIN5DXAPfL4du7QHmqCdIzQWTpwfr66abDaX4uLis7M

Yes, the gui stops coming up after the upgrade to 11.04 (Ubuntu Natty), unless I choose the Ubuntu Classic (no effects) option at the login screen.  

Reinstalling (deleting the folder and unpacking the tarball again) changed nothing.

Edit:  Here's the Launchpad bug report: https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/758398