Looking just like a Lego brick, the Kiddy Mini Speaker looks like the perfect portable speaker –  assuming you don't want hi-fidelity sound. Measuring in at 1.61″ (W) x 0.98″(H) x 0.67″(D), it has its own USB-chargeable battery.  Its little amplifier pumps out a whopping 0.8W of power for up to 6 hours and will work with any device with a 3.5mm stereo jack.  This would be perfect for my Thinkpad Tablet because the inbuilt speaker is nothing short of pathetic.
The Gadgeteer, Kiddy Mini Speaker
