I've owned a 32" Sharp Aquos for about five months. Over the past month or so, I've noticed what can best be described as a dim beam of purplish light shining down from the top right corner of the screen. It does not seem to affect picture quality at all.

I can't decide if I'm seeing things or not- has anyone else ever heard of this?

Sounds like backlight bleeding.

Is this something I should worry about? Does it have the possibility to get worse and affect picture quality?

Well, it can't be fixed without some major repair work and proper shielding. If it gets worse, I'd start to worry about something going wrong with the build of the display. It will only affect PQ in the area its located, and probably then only minimally. It's something to keep an eye on, but not a panic about.

Google your model number and backlight bleed and see if others are having similar problems.