I've played quite a few but then I usually don't have the patience to play more than one route.
Some I've played: Joker Kuni no Alice (and other Alice in Wonderland by QuinRose), Hakuouki series, K Project's game, Norn 9 etc.
Each has their own charm :3
Hm.....I would prefer the original work (in some cases manga/novels) but then with anime, and with good adaptations, they would bring the work alive. That and, I follow quite a few seiyuus and the popular works would often feature them so...