At one time when I was thinner, had a full beard and wore tailored double-breasted suits, I was a dead-ringer for Larry Ellison (when he looked like he did at that same point in time).
I walked into the Oracle building to get a certificate and couldn't understand why all the staff members were just staring. Then a co-worked picked up a magazine with Larry on it and... it could have been me!
I happened to have a friend (a previous co-worker) that looked just like Bill Gates. So we decided to have some fun when the big tech convention came to southern California. We dressed up, started at one end of the long hall and walked all the way to the other and out the door. The entire time we didn't look at anyone, we just had this very intense discussion between ourselves the whole way. Some friends planted to watch were laughing like crazy at the reactions. Wish they could have filmed them, we were too busy playing the parts to notice!