if you buy the humble indie bundle 3, you get a free trial that lasts untill august 14th, you have full access to all the features and multiplayer.
in case you dont know about the humble indie bundle 3, you can pay what you want for 5 indie games, you get a free trial pass for minecraft with every purchase.
if you pay more than the average (currently 5.11 USD) you also get all the games from the humble indie bundle 2.
there are some great games there! give it a try.
HERE is the PCGamer demo, i dont know if it works or if its updated..