Droplet

Here's a nice flash game with a very 8-bit feel, made by Photon Storm.
Apart from being pixel-art style - it has a really nice gameplay. You can check the game here.

Paint 3D

You might want to take a look at a very nice 3D editor called Paint3D. You can create 3D images (and 3D pixel art) the same way as in ordinary Paint - how cool is that?

Some beautiful old art from vintage video games

Some time ago there has been a great post on webdesignerdepot.com, talking about video game design over the decades.
To me the begining part was the most interesting - games in the early 90's got a very nice pixel-art gamearts.
Check the list for yourself at webdesignerdepot.com.