I recently discovered that the Dolphin emulator is a lot better than what it was back in the day. Now, it can play Wii games better than the Wii itself!
Over the weekend, I played 8-9 hours of The Legend of Zelda: Twilight Princess. Only the UI was in HD, though–the 3D-rendering looked like it was only at 480p with no AA or AF. Super Smash Bros. Brawl worked fine at 1080p and actually rendered in HD.