Believe it or not there is a lot of good old fashioned adventure gaming to be had on Microsoft's XBox Live Arcade. As of the time of this post there is:
Secret of Monkey Island SE (Tales of Monkey Island is said to be a possible XBLA port, they are out on PC and Wii now)
2 seasons of Sam & Max (11 episodes)
4 episodes of Wallace & Gromit
2 episodes of Penny Arcade (these are kind of adventure game & simple rpg)
They average about 800 microsoft points each (about $10), with the Sam & Max seasons going for a bit more (1600 microsoft points) due to their larger size (5 and 6 episodes each by season).
I've been playing Monkey Island and its been a total retro experience. The same settings, story and gameplay, but with 720p and hand drawn images instead of chunky monkey CGA. =)
