Two of the most memorable compliments I ever got were...
When I was about 15, I was throwing a football around with my buddy. His sister and her hot friend walked by and the friend walked up to me and told me I had a great ass. Since she was so hot and and my buddy was cracking up.. I had no idea what to say back. I think I garbled out something about a potato... she laughed, and I avoided her for like a week.
When I met my wife, (obviously g/f at the time) she said she wanted to meet me because I looked identical to some guy in one of the day time soap operas. She said I must hear that all the time, but I never did.
Then a week later when I was shopping, this teen girl and her mom came up to me and said I was a dead ringer for this guy. This was like 15 years ago so I can't remember his name...
Edit: did a quick Google, it was Austin Peck.