I am not sure if this qualifies as a spy gadget, mind you it might be useful for underwater spy missions, the Head Mounted Waterproof USB Camera.
The Head Mounted Waterproof USB Camera is a tiny uSB camera that attaches to your head with a strap, it is fully waterproof and can record up to 3 hours of video at a 320 x 240 resolution.
Unfortunately it can’t record any sound, so you might just have to use this one for underwater spy missions.
The Head Mounted Waterproof USB Camera is available for $135 from Thanko.
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