A variation of both the "pay for $3.75 in 3 dollars and 57 pennies" and the "let me find my checkbook" person is the little old lady (always, a little old lady) who gets the total and then starts to rifle through her purse.
Now, little old lady purses have like a thousand pockets, each of them needing to be separately zippered open. She goes through pocket....by....pocket....by....pocket. Finding a dollar bill here, a fiver (if I'm lucky) there, a couple quarters... Makes the cashier keep a running total while the lady asks every couple minutes "how much more do I need." Just shoot me now.
Mrs. Milepig is actually one of those who likes to haul out a coin purse and count out the exact change. Drives me crazy and I pretend not to know her when this happens. She seems to have an endless supply, and seeing as how she's always using it up I've never figured out where her change COMES FROM to begin with. I think she's stealing it from my stash.
Back in the day, the toll booths on the Illlinois tollway had those fun rotating boxes that you threw your change into. (Maybe they still do, we have EZPass). They took pennies and it was a great way to use up spare chagne. Toss in a handful and the machine went grind...grind...grind while it slowly counted the pennies.