Most of them are pretty awful, to be very honest. The only ones I can truly appreciate are Rafael Dyll's remake of X-Out, which introduces the heavy militaristicness (is that a good word?) the original lacked because the hardware couldn't produce it, and Markus Schneider's remake of Supremacy, which features the etherealness you would picture with God creating the universe where the game is situated. There are more nice ones out there, though.