Jim Logajan wrote:
The following thread on the Van's Air Force web site was of general enough
interest that I thought it worthwhile to bring it to the attention of other
pilots:

http://www.vansairforce.com/communit...ad.php?t=24147

Would be quite useful if it really worked. Of course there would still be
strikes with inattentive and near-sighted birds. ;-)

Entertaining thread this turned into. Anyway, here's a nice illusion.

http://img408.imageshack.us/img408/8067/imagegm1.gif

Concentrate on the + in the middle.
An illusory green dot soon appears.
Moments later, pink dots seem to disappear.