Aliasalpha: My old monitor had a pixel that wasn't dead but wasn't at all well. Often times rubbing around the affected area alleviated the problem. Weird to have to give a piece of computer equipment a massage but it worked...
I had that on my old laptop, except it wasn't just a pixel. There were entire lines across the width of the screen from the top that were just some random colors and weren't affected by the screen update.
However, if I rubbed the screen it would go away and just display the normal image temporarily. It would go back to broken as soon as I stopped rubbing and pushing on the display, though.
Then I discovered that if I flexed the screen just right, it would disappear for some time (only to suddenly come back). So I started flexing the screen by bending it a little in the edges to make the defect go away on a temporary basis.
Then, one night, approximately 6 weeks before I had to deliver my Master's Thesis, I flexed it a little too hard.