For me, I'd have to say Old School X-COM (UFO Defense, TFTD, X-COM Apocalypse to an extent). I love them in a way that I just do not enjoy NewCOM, but the interface was quite possibly based on the recovered works of a 13th century scribe, and is very difficult to get used to for an unfamiliar player.
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You do not start the game with a research already active, this tends to happen mostly in new games. That said, I've seen cases where someone started a project and forgot to assign any scientists to it, which is functionally identical to this.