Check out www.chromasia.com
If you have a big monitor and open the page with you browser maximized the image will be large. If you shrink your browser window down and refresh, the image is smaller.
I've done some research to find the java script that grabs the window size but I don't have the web skillz to figure out how to use it to do something similar to the gallery I am working on... www.the9clicks.com
Anyone want to collaborate on this (or just tell me how to do it)?