As you may or may not know, I am a big fan of Exotica, Tiki and Polynesian Pop. In that vein, I stumbled across a great Flickr group that I really enjoyed.
Exotica Wallpaper. Atmospheric images of Exotica, Tiki, Tropical Landscapes & Polynesiana.
Scenes of Exotica from the South Pacific that come to mind when listening to the tunes of Les Baxter, Martin Denny & Arthur Lyman.
The minimum dimensions of images are 1024 x 768 you you can usually find some great wall papers for your computers. Lots of great palm trees and sunsets.