MMr - friend had one for years which I loved. Remake opportunity hit and its a permanent fixture in my game room.
Houdini - played it at SFGE and had to have one...still love it.
TNA - Played the white wood at SFGE and had to have it. Paragon was my go to old school game and as soon as I got home it left and I started watching for someone backing out of their spot in line. Few weeks later I was in line and I love it so much so I am making mods for it.

I have bought plenty of games I had never played be I purchased and most are gone. I have bought a few games twice but these three are staying a while.