Battletech
Been teaching my 8 year old son how to play and he loves it.
I still have all my Battletech stuff, including the first tech manual that they had to republish after FASA lost the copyright to certain mechs (ie: Maurader). I even got all of the 1st run of Battletech Dark Ages clix, which is fun. Haven't really found anyone interested in playing classic Battletech after I moved, let along the clix where you have to collect the figures to play. I'm also on a kick to try to get a group for Heavy Gear (tabletop or PnP RPG) and Jupiter Chronicles.
Thanks to this thread, I just picked up Settlers, Dominion, and Carsacann. The girlfriend likes Civilization, and aside from Mario and Rock Band that's all the video games she likes, so I figured those three would be a good starting point for non-traditional board games. I tried one game of Khet with her, and she swore that one off My friend wouldn't even come near it. I also picked up Arkam Horror for a cooperative Lovecraftian twist. I played way too many games of Monopoly, Life, Sorry, and Trouble as a kid, so I'm looking for something with a bit more umph.