This gadget is awesome. It's a Belkin TuneTalk™ Stereo voice recorder for iPods. When you plug it into the bottom of your iPod, you can record voice memos in a snap. And there's no set-up or anything. When the voice recorder is plugged in, a new category called "Voice Memos" shows up right on the main menu. To run the recorder, you simply use the iPod's scroll-wheel and select button to follow the prompts on the iPod's main screen.
I picked this device up at the Apple Store for a business need. It wasn't cheap - maybe $60 or $70? But, once we heard the recording quality (which is surprisingly fantastic), Isaac & I have since used it for video voice-overs and for recording our children's sweet little voices - while they're still sweet & little. The voice files created are easy to move into the computer for storage as well -- they import right into your iTunes library.
I highly recommend it. See your local Apple Store for more info. And, here's a current list of iPod models this recorder should work with.