Yes, this works very quickly and effectively, but you've got to avoid the eye twitching bit to keep the effect alive.It starts to fade very quickly but then the colours intensify if anything. Tried with each eye and both eyes.
Aaaarghhh! I must have Non Troxler's fading
Thanks for that idea. The Wiki one works for me and the one posted here doesn't. I got the same effect of the colours, esp. yellow becoming brighter as mentioned by @Tunn11. The one here started to look like an image of two people side by side.There's a Wikipedia entry with an example and that works for me but this one doesn't. The colours are slightly different so perhaps that has some bearing on whether you see the effect or not.