For a while a couple of stores in Pennsylvania were dealing double deck, with the rules being what PA law says they must be- S17, DAS, LS. That was very close to +EV and was +EV with good playing indices. There were rumors of a SD game being dealt too but I never saw it.
The 4D game with the single pass shuffle at Tropicana AC.
Triple Down Day at Mohegan Sun.
Maybe the best I've ever seen at blackjackesque games was in a store where they were dealing Multi-Action BJ and Double Exposure right next to each other. This girl dealer, she apparently got the two confused and was dealing both her cards face up at the Multi-Action game. I was trying to figure out ways to keep other players from sitting down and I got lucky and didn't get a snitch. Sat and played until I heard a phone ring and a pit boss running over screaming.