I was pleasantly surprised when I noticed that you can have a lot of oldies on your DS, and lots of Amiga games are playable, even if UAE would be too tricky to port on the DS (because of controls, mostly, and CPU). James Pond 2, ...
First, there are a lot of nice retro games (Namco Museum, Midway Arcade Classics...). Nothing to do with the Miggy but still, old and genuine stuff
Second, you can buy secondhand GBA cartridges. I bought myself Speedball 2, Klax, and Marble Madness. All excellent ports.
Third, there are a lot of homebrew ports of Amiga games: Rick Dangerous, Lemmings, Magic Pockets & Cadaver (both in work, by me
Last but not least, you can use a Sega Genesis emulator like jEnesis. It's super fast (I could not believe it) and look at the Amiga games with a Sega Genesis port:
I could test a few ones (some don't boot with the emu):
Gods: runs perfect (although the game is too fast, like in the SNES)
Chaos Engine/Soldiers of Fortune: game runs fine, problems with scrolling.
Chuck Rock: perfect (except for the dinosaur that no longer drops his load, I guess this was not consolly-correct)
Chuck Rock 2: perfect
Leander/Legend Of Galahad: perfect
Xenon 2: OK
Mega SWIV: perfect
Lotus / Lotus 2: fine
Battle Squadron: perfect!!!
James Pond: perfect
bad news: Zool, Cannon Fodder, Desert Strike, Gauntlet, Killing Game Show, Mortal Kombat won't work. Well, maybe later
Ok, hoping not to be too off-topic. Bye