If I Was Invisible?
Thats no more a question, the question is "When Will I Be Invisible?", yes one day you'll be able to pull a April fools joke with a sheet that makes you look like your not there.
Although more security camera methods will more likely be needed to track bad guys under the sheet that makes them look like nothings there.
http://www.voanews.com/english/2008-08-12-voa69.cfm
I have this feeling those sheets are going to cost alot though.