I just came across a pretty sweet visual illusion video from ScienceForum that caused my vision to blur in a way that reminded me slightly of how my vision used to work when I would take a small dose of LSD (it's been a long time since I've tripped, but I can remember the feeling pretty well). I highly recommend watching this video!
So, hold on to your britches there, sports fans. This video is going to take you for a little bit of a ride. Okay, maybe it's not that crazy, but you should feel some visual illusions that will make you think you're hallucinating (note, watch this in full screen and with no other distractions):
Pretty sweet, huh?
Tricking your eyes and your brain to momentarily perceive the world in such a blurred way is fun. Of course, this video just causes your vision to shift a little bit, so you're not getting all the fun (or terror) of deeply hallucinating.
Messing with our perception of the world can be fun. Our minds are not infallible in how they interpret the inputs from our sensory organs, and yet we often feel certain that what we think we see and hear and feel and do is the exact truth. Visual illusions are awesome since they force the observer to test their perception.