You can upload an avator to show at the side. The pic has to be re sized quite small about 80pixels maximum but there is a current thread somewhere on how to do this with a website link. 'Help someone'
We do not have signature pics on HC as they can be awkward for people with dial-up as they take ages to download.
You can upload to your profile by clicking on the hamster pics in my hamster central at the top of the page.