Picodrive : Road Rash II - This game holds up pretty well, although doesn't quite get full speed because it requires the "accurate renderer". I also play NHL '97 now and then.I was playing Phantasy Star IV for a while, too, but took a break from it.
Beat2x - A bit of lag because of the LCD, but I've adapted to it.Haven't been able to get past Song 6 yet, that one is tough!