I'm racing against the clock here to get this particular delta posted before Ian uses up the entire world's supply of cool deltas... Hopefully this post makes it up in time!!

The Okavango Delta of Botswana is unusual because the river that feeds it never makes it to the ocean or even a lake. The basin it debouches into is dry as a bone, part of the Kalahari Desert. The classic features of a delta (distributaries, etc.) are still there, but it is a singular feature on the planet Earth to have a delta of this size dry up in the middle of an arid area.

The water provided by the delta encourages plant growth, making for high-contrast satellite photography, as well as making it a refuge for wildlife.

Interestingly, there are ~east-west linear features running across the un-delta'ed landscape, and I'd be pleased if someone could explain what they are. Also, check out the southeastern part of the delta, where several large parallel fractures (trending northeasterly) appear to control the drainage pattern.

Flash Earth location is here:
http://www.flashearth.com/?lat=-19.64623&lon=22.842506&z=8.2&r=0&src=yh