I love emulation, especially on consoles. Playstation on my Dreamcast. Sega Genesis on my Playstation 2. NES on my Playstation. Blisters on my fingers! Warts on my ... oh my, I've said too much.
I highly doubt that Sega's intention with the Dreamcast was to make the most easily programmable and hackable home console of all time, but that appears to be exactly what they did. While mod chips and boot discs were originally required to play imports, backups and homebrew games on the Dreamcast, everything I've seen over the past few years boots itself up off a CD-R on a completely stock system. Oops. Combine that with an army of dedicated programmers and Sega fans, and you end up with a complete library of emulators freely available for download for your Dreamcast.
Recently I stumbled across DCStella, a port of the Atari 2600 emulator "Stella" for the Dreamcast. The image I downloaded came with a semi-complete Atari 2600 ROM collection, so once the disc is burned you've got a self-booting emulator for your Dreamcast with every Atari game on it. Sweet!
Once I started playing games ... not so sweet.
I can remember getting new Atari 2600 games as a kid (and even as an adult!) and playing them for weeks on end, so looking at a menu with 600 different Atari titles on it can be a bit overwhelming. I skipped to the end of the list and began looking for titles that looked familiar.
Up 'N Down: I've always loved this game both in the arcade and on the Commodore 64, but had never played it on the Atari 2600 before. Once the game came up I was treated to some loud blasts of noise and some horrible graphics. Maybe that's what Up 'N Down looks like. I exited this game quickly and moved on.
TRON: Working backwards, the next game I wanted to try out was TRON. In TRON, my character would not stop running left. I could throw my disc, but usually to the left. I ended up in the top left hand corner of the screen with people attacking me in the back as I kept running into the wall over and over.
Surround: Same thing. The controller in port one controlled player one just find, but player two kept moving up and to the right. I had no controller in port two of the Dreamcast. When I plugged one in, nothing changed.
Superman: Couldn't even get this one to start. It just kept making Superman's X-Ray Vision sound over and over and flashing around to different scenes. Not even the Man of Steel could get this to work.
Strawberry Shortcake: Shut up. My sister had this game when I was a kid. Surprisingly enough, this game loaded up and worked okay, but the sound was horrible. Of course, the point of the game was to line up different Strawberry Shortcake characters to get the game to play songs, so with garbled sound the point was lost.
Space Invaders: Actually, Space Invaders worked fairly well. The sound sounded a little off, but I could live with that. My only concern is that the game was not running at full speed. It's been a while since I played Space Invaders on the 2600, but I don't remember it being that easy. I cleared the first five or six waves on one man. Once the levels without shields began, the game was running significantly slower than full speed.
As it currently runs, I wouldn't recommend checking out StellaDC for anything more than novelty reasons. One would think Atari 2600 roms would be easily emulated on such a fast system, but this was not my experience at all. There are lots of great Atari emulators available for lots of different platforms (both PC and console), but this is not one of the better ones.