Not to mention Static, though it's not coming out for a time. If you want to check it out at http://www.static-thegame.com
It's different, but you are not going to find any game that matches Fallout. Perhaps if you were more specific about what you want in the game (Turn-based RPG system, story, atmosphere, ect.)
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"It is difficult to say what is impossible, for the dream of yesterday is the hope of today and the reality of tomorrow." - Robert Goddard
Man i would like to really get my hands on Wasteland... But its so impossible since it was made in 1987. But i dont think Wasteland is a wannabe since isnt it the legitimate predecessor to Fallout? Or so ive heard....