On the cheap end you aren't going to get many features. Still, I recommend the Garmin Geko 201. Don't buy the Geko 101, it has no PC interface. Don't buy the 301, it has extra features that are not really worth having.

Geko 201 Pros:
small, light, waterproof
robust
uses AAA batteries and will run off NiMH cells
has a PC interface to transfer data back and forth
you can upload routes and waypoints and follow them
cheap

Cons:
Batteries last for only 1 or 2 days if left on constantly
Power button can sometimes be activated in a pack (to turn unit on)
No topo map capability, but it records a trail of where you've been

I am sure there are other pros and cons, but I've used this for cycling, hiking and driving, mostly to collect data, but sometimes for getting to a destination waypoint. It's tiny and works well.

IMHO a GPS *should* be simple, and you should have the skill to use it in conjuction with a map or other navigation aids (you should also have the skill to use the map *without* a GPS).

Anyway, that's my opinion. Carry spare batteries if you are going away for more than 2 days.

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