By now you have probably all seen the right brain vs. left brain spinning lady brain test.
Many people believe it is a scam and that the lady actually changes direction about every 30 seconds or so.
There are a few problems with this:
First of all, it's an animated gif, so if this were the case it would be very obvious and time-able.
Secondly I have tried it with many people where they see the lady spinning in the complete opposite direction as myself at the exact same time.
Whatever you think, check it out because it's pretty cool!
Note: I couldn't get the stupid animated gif to work on blogger so here is a link to the youtube video (which I know is against my argument above). Do some searching around on google and you can find the video as well!