It certainly isn't the first time someone has snuck on to the App Store, and I can almost promise it won't be the last, but if you're big into grabbing things you "shouldn't" have (per Apple's approval process) then Awesome Baby Names [$1.99] is something you need to snag immediately. What initially appears to be a very simple and silly baby naming app is actually a fairly full-featured Gameboy Advance emulator.
Accessing it is simple, load up the app, tap the top left corner three times, the middle button once, then immediately above that once. Presto, you're thrown into a ROM listing for a Gameboy Advance emulator. You'll need to use iExplorer or something similar to load a Gameboy Advance bios as well as the actual ROMs into the app, but once you do that, it's (reasonably) smooth sailing.
For help with getting this all running, definitely check out the thread in our forums. Admittedly, getting this all working is a little trickier than playing your typical iOS game so if fiddling with your phone's file system via iExplorer sounds over your head, this might not be for you.
Update: Aaaaaaaand just like that, Awesome Baby Names joins the many other similar trojan horse apps that have been released. Apple seems to have just pulled it from the App Store. If you were able to grab it, store that .IPA somewhere safe. I recommend snagging a free Dropbox account and just using it to permanently store apps like this so you'll always have a copy in the cloud if you ever need it again.
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