Happens to me daily. Even people I know well but haven't seen me in the last few months. The best ones are where people look straight at you but don't recognise you until you speak.
One guy even did speak to me and tried to find out how long I had been at my job. It took him a good five minutes to realise it was me: a colleague I had known for at least two years, but again not seen in the last few months.
To be honest, while I do find it funny I am also starting to find it a little weird.
Security blocked me from getting into work last week because my ID photo did not match my new face and the guard did not believe it was me.
Psychologically these types of changes are in many ways more challenging than the weightloss. So you 100 pounders had best get ready for that.
At the beginning, I used to think I would just be a thinner me. I have actually become a different me...in some ways better and (perhaps) in other ways worse.
This guy gets it:
http://www.charlotteobserver.com/201...ist-tommy.html