A free-to-play rogue-like MMO.
For the little bit I played, the graphics, although 8-bit-looking, were nicely made and it run mostly ok. The loading process, though, froze my Firefox for a good 20 seconds.
Edit: Ok a bit more playing later and it seems they have lagging issues. Once I joined a map with a lot of people (about 75 of the maximum 85), my magical spells were lagging hard and movement was erratic. I’d drop all keys and my character would still move around, fires were going to places where my mouse was 2 seconds ago… That kind of mess. I can’t fully blame their server load or game mechanics (they should have a huge load right now, since the game was featured in Ars Technica) ‘cause I played on a Mac and it’s a widely known fact that Flash on OS X is incredible bad.