I have floaters in my eyes (
http://www.allaboutvision.com/conditions/spotsfloats.htm ) to start off, and for those who have these as well you will know exactly what im talking about.
So I just bought Grand Theft Auto 4 last friday, and I played in on my 19" HD TV, since the screen is small i usually sit close to the screen. Well the way GTA4 is made it looks like it should be HD graphics, but alot of the lighting in the game makes it look blurry and hard to focus on. So about 2 hours later (this where the floater guys will know what it looks like) it looked like some of my floaters where stuck in the middle of my vision, so i stopped playing and walked around to let my eyes rest. The area in which the floaters were stuck grew and spread all the way up and down the left side of eyes (both eyes), it looked like a huge semi circle of a thick floater that would not move.
Once I noticed this in both my eyes I knew it had to be a brain problem. I head over to my eye doctor and by that time the weird phenomenon had gone away( about 20 minutes) and my eyes felt like they were just stabbed with hot needles. The eye doctor told me that my eyes were perfectly healthy, and that what i described to him fit the description of the optic nerve spasing out and the lack of blood to the eyes would cause weird shapes in my vision just as i described. He said that it usually happens with people who are stressed out or putting alot of strain on their eyes, such as the video game. Its not the eyes but the center of vision in your brain.
I thought I had a brain tumor!!

Found a link with the symptoms on this site:
http://www.allaboutvision.com/conditions/ocular-migraine.htmOn the flash player on the second link, if you cover the right side of the screen thats exactly how it looked.
Anyone else experience this?