Whenever I try to go to wikipedia.com, access my school homepage or watch videos on the internet (besides youtube), etc., I get this strange 1/4 inch by 1/4 inch little box in the upper left corner of my screen. The top left portion is black and the bottom right corner is gray. What is the deal with this? I'm assuming it's a virus.
An image of this happening in firefox:
http://img86.imageshack.us/img86/4241/73358385mu1.png
In IE the browsing screen just turns white with no box. It's really quite debilitating.
Any help would be greatly appreciated