A lot of (social networking) websites use avatars to represent users. Technorati, last.fm, Ohloh, Google Mail... they all allow you to upload a small image and include it in your profile. Whenever somebody is looking at your profile they'll see the image.
I would really like to use a picture of myself with a "Scanner Darkly effect" or "Sin City effect". There are some tutorials that explain how to obtain this effect but the "Let's skip ahead about an hour. You've been busy, and we've got this so far..." is not really encouraging for a graphics newbie like me. The chance that I end up with a nice result is close to zero.
As a cheaper (time is money) alternative I tried a couple of online caricature makers but - even though these tools are really easy to use - the end result was never quite "me".
The quest for a nice (and personalized) avatar continues...