There's a similar product that's been mentioned on the forum before.
Looks like both the accessories work with only certain cases, though.
I generally use my Jambox Bluetooth speakers, but in a pinch I use an old Apple gift card cut on an angle. I can firmly slip it between my iPads and their cases, it's free and flat, and pretty much indestructible. If I lose it, I'll cut another, lol.
This one is magnetic and much cooler. It also puts the iPad into sleep mode like the smart cover. But yeah in a pinch that would work too! Lol!
I've been using a SoundJaw for a few months now and it works great with my GreatShield back cover and the SmartCover. Less obtrusive than this one though. I forget it's even on.
NOTE: The originator of this thread is the inventor of the linked product.
Just so everyone knows...
Can we buy these yet?
32GB WIFI/3G 'The New ipad'