One of the more droolworthy (literally) gadgets we've seen this year is this Sandisk Sansa Shaker, a 2.5-inch tall MP3 player designed for stubby fingers and curious ears. The $40 device comes in pink or blue, ships with a 512MB SD Card, and plays MP3s through its built-in speaker or up to two pairs of headphones.
But the real fun starts with the navigation. In order to skip a song, you just shake the player until it advances to the next track. A circular band around the player can also skip forward or back among between songs, which most likely play in alphabetical order (you can trick players like this into playing songs in a specific order by adding numerical prefixes to the file names). Another circular band handles volume. Rounding out the specs is a 15 hour battery life from one AAA battery.
The interface is innovative, and the price is right; my only concern is about volume levels. Kids have way more sensitive ears than adults, generally hearing frequencies well above the generally-accepted adult limit of 20 kHz because their ears haven't yet been beaten up by jackhammers, walkmans, concerts, and the like. I emailed asked Sandisk whether this thing has a volume limiter to preserve kids' hearing, and will post their response here. (Cautious parents could always withhold the headphones and let junior listen through the speaker.)
Update: Here's a response from Sandisk on the volume issue:
