I was watching Click recently (a BBC technology News Item) and they brought a really useful site to my attention.

The site in question is www.picnik.com - this is a really handy online tool that allows you to edit picture size and add a number of effects to the image. Useful for resizing blog images as well as resizing photos before printing (and probably a whole host of other things I can't think of right now).

If your blog image is too large, why not check it out and see if you can make it a more suitable size.