Lots of stuff qualifies as this for me. About the only games that look bad to me are first gen 3d console games, mainly N64 ones. 2d games age far better than early 3d, and even some 2600 stuff still has a look I appreciate today. Once you get into decent 3d, as long as the texture work is good, I'm fine with up-scaling the resolution and still playing the games.

Pong looks awesome.