anaggie,
Check out the following speakers at the Apple store:
TravelSound for iPod shuffle:
http://store.apple.com/us/product/TR...mco=MTIxODk3Mw
What I like about this one is that the shuffle fits on top and since the shuffle connector is a simple headphone jack you can also use a headphone extension cable to plug this speaker into your laptop or any other iPod via the headphone jack. Rechargeable and 15 hours of battery life.
Travelsound for iPod nano:
http://store.apple.com/us/product/TR...mco=MTIxODk3Mw
This one works with the wide nano (4th generation) and current 5th generation, but not the 3rd Gen nano.
I have the one for the shuffle since I wanted something to use with my laptop and iPod via the headphone connector. I own a shuffle and 5th Gen iPod.
Hope this helps!