Gadgets don't come much more manly than the tank. Even MP3 players can be made extra-manly by tacking on tracks. Cower, then, before the Mint Tank Music Player: it's Action Man's iPod.
The Mint Tank is a concept from mintpass, which we spotted at design blog Yanko Design. It features urethane-coated caterpillar tracks that wrap around the speakers. An ultrasonic sensor detects obstacles and a pyroelectric sensor detects your body heat and follows you around. The sensor can detect different heat signatures and so can be programmed to follow different people.
You can also control the Music Tank with a Wi-Fi and Bluetooth remote control, and either stream music or fill the Tank via USB. When first switched on, the Tank will explore the house, building a map so as to find its way around in future.
With a squadron of one or more Tanks, the individual units will detect each other and play different parts of the music, creating a surround-sound effect.
So who would win in a fight between the Music Tank and the Sony Rolly? We wouldn't bet on Rolly...