didn't know I could do it that way neil, I've always done it the other way. You can do it so when you click on an image in your sig it takes you to a site too. You replace the text with img brackets and the image address.
[URL=http://www.kipax.com][IMG]http://img148.imageshack.us/img148/7195/gallery1bx0.jpg[/IMG][/URL]