Quote from 5haz :

I have had a very sharp, sudden bout of extreme dizzyness once while playing LFS, I had my headphones on so I could only hear through one side, which feels a bit odd, then suddenly bang I nealy fall off chair, no idea what happened, never happened before or since.

I had the exact same thing once before while playing LFS, but my vision was affected too.

One thing i get regularly, is if i look up at the sky on a bright day, i go light headed and start to lose my balance. Then i get searing bright light in my vision, and go blind for about 5 minutes. I dont know if its normal, as i've never asked, but i get it occasionally and its very annoying.

if i don't east in 6 hours before playing something like portal, then i'll feel sick and my body temp raises.

Quote from Shotglass :

you should try playing descent

Yeah Descent, luckily i'm not prone to motion sickness, but Descent always gave me a dizzy feeling if played too long.