Mythos is a fun online game that I picked up from Amazon, didn't expect it to be great but actually it is really good. I am having lots of fun playing on it at the moment.
"Mythos lets you experience exciting Hack’n’Slash action in a comic book style atmosphere with no monthly fees. Hunt down monster after monster on your own or with friends in murky, randomly generated dungeons."
Windows Vista / XP
For ages 12 and over.