ANSWER:
Yes you can!
The image needs to be no larger than 16x16 pixels and saved in the file format "favicon.ico"
You can either make a .jpg and then change the file name to .ico - or you can use any one of free favicon generators found online via a google search.
COOL - NOW WHAT DO I DO WITH IT ONCE I CREATED ONE?
At present, you'll need to contact Webninja support and provide us with your favicon so we can apply it to your site.
tags: favicon, browser_tabs, icons, favourites