How to make infrared goggles

This one is from Bill Beaty, a fixture in the Seattle fringe science scene. I wasn't aware that the human eye could see in the infrared range but appearently we can. Your basic instructions to converts some welding goggles to infrared filters using lighting gels can be found here:

http://www.amasci.com/amateur/irgoggl.html

Cost? $20. Walking around is broad daylight looking like a mad scientist? Priceless.