Torchlight looks rather nifty and is going around as the latest fun little game. It seems their model is to bring out a single player game then bring out an MMO latter, based on profits. If you think about it, world of warcraft worked from much the same model with it's RTS games (admittedly they were multiplayer, but like just a handful, so not an MMO).
It sounds like 'Fate', as in it has a pet which fights for you and also sells loot for you, which is exactly what fate had. I'm not sure if the development teams are the same.
But there appears to be no demo? Or have you heard of one!? Please leave a comment if you have!