Without a doubt, the comment I get the most is, "You sure have your hands full!"
After hearing this for the fifteen millionth time, I got tired of answering with a lame, "Yes.  I do."
Like, what else can I possibly say to that?
"Ya think?"
"Huh?  I've only got five, you should see my sister she has 11."
"You talkin' to me? "
"Wha...don't tell me those stinkin' kids are following me again."
"Oh, no, they are all little blessings sent straight from heaven."  That said while gritting my teeth and wrangling a screaming toddler from the overloaded cart at the grocery store.  Honestly.
One day it just popped out.  I must have had just enough sleep to be thinking coherently.
"Yes.  I have exactly one handful."
Hardy, har, har.  I explained it to the kids later and we all had a good chuckle.  That has become my stock answer. My 'handful' and I are always eager to see the reaction I get with that response.  We giggle about the quizzical looks that I get and it's turned an annoyance into a game.  Instead of them being a 'hand full' and nuisance, we walk away from the exchange with smiles.