The method i've been using for a while has nothing to do with the server loads as it resize the images with CSS (instead of javascript) and it resize them before the page completely loads.
Only missing thing is the automatic linking to the original image dimensions. Check this page for example:
http://www.msxlabs.org/forum/fantazi...tml#post682559
The picture in the first post is resized (
actually shrunk) to 728px width. It's actual width is 1024px.