Garmin Geko 101 GPS with Waterproof Exterior (Yellow)

Not the best GPS in the world, but probably the cheapest.

Features:

Compact 12-channel GPS receiver
High-contrast display (100 x 64 pixels)
Stores 250 waypoints
Waterproof: submersible for 30 minutes in one meter of water (IEC 529 IPX7 standards)
Easy operation: five buttons for one-hand use
12-hour operation on 2 AAA batteries

http://www.amazon.com/exec/obidos/ASIN/B00007MIKM/

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