I recently bought an Atari 400. I found it at a garage sale for $10. It came with controllers, all the hook ups and 8 games. This is my first experience with vintage computing. I was surprised that the graphics were better than the 2600 and the two were out at about the same time.
Many of the games are the same old boring Atari titles, Missile Command, Super Breakout, Pac Man, Space Invaders, Asteroids, Galaxian, and Frogger. Are their any original titles for this computer? I would like to use it for gaming every once in a while but I would like to find a title that I can't already play on my 2600,5200, or 7800.
Also is it worth getting a disk drive, tape drive, and a printer. Is there anything interesting I can use it for besides gaming?
Wecome to Atariland, Fred.

The Atari 400/800 is my favorite vintage computing
and gaming platform. You should try to find an Atari 800 with 48k of RAM (most 400s have only 16k) so you can run more programs than just cartridges. Most of the cool stuff is on disk.
Indie software developers made thousands and thousands of cool and original games for the Atari 8-bit computer line over the years, and you can download disk images of most of them from places
like this. For maximum funitude, you should buy an
SIO2PC cable so you can run the disk images directly on your Atari 400 or 800. Sadly, not many games run in only 16K of RAM. You really need an 800, 800XL, 130XE, or 65XE, or even XEGS to get the most out of the 8-bit Atari scene.
I think
http://www.atarimax.com/ used to sell multi-carts with games already on them, although many games require more than 16k. They also sell awesome 8-mbit flash carts where you can put many games on them at a time for use in your Atari 8-bit. I use those a lot to play games.