Today only, the Garmin GolfLogix GPS costs $169.99 at Amazon.com. With free shipping, that's a $118 overnight drop and the lowest total price we could find by far.

This golf-oriented GPS unit helps you calculate yardage distances, even on greens, so you can choose the right club.
It promises excellent visibility in direct sunlight and is waterproof and shockproof.

Software is included (PC/Mac) to download any of more than 15,000 golf courses.