Hi,
I recently stumbled upon Voki (www.voki.com) which seems like a nice widget. It comes from Sitepal (www.sitepal.com). Actually I have used Sitepal in past. Unfortunately it didnt work great for me (nothing wrong with their product, but it was just a bit irritating for our customers). However I can see good potential for a concept like Voki which is more of a "fun" concept and can be extended to social networking.
I created a voki character of mine to try it out. I could made this stuff within five minutes flat. So, it is simple to use as well 🙂
Your customers may be more inclined to view charatcers on my site as opposed to Sitepal’s.