I'm going to say Assassins Creed because the concept is awesome and I was looking forward to all the games being in different times with different characters and to use the assassination skills on different types of people. But now we are stuck with Altair and Ezio in the same times and the combat gets very dull after awhile.
Edit: Now that I think about it Mindjack is also up there, the game concept was something new and I almost bought it when I saw it in gamestop. It's sad that it sucks because that was one of the few games that pigued my interest on concept alone.
Edit: Now that I think about it Mindjack is also up there, the game concept was something new and I almost bought it when I saw it in gamestop. It's sad that it sucks because that was one of the few games that pigued my interest on concept alone.