Surely this has been done, but if so i can't find it, so what the heck I'll start with mine.
Sophomore year of college (1995), finals are coming up and the girl that I like (now my wife) and I both live on campus. She doesn't have a car, I'm driving a 71 chevelle malibu, with a quart/tank of gas 307. I ask her if she wants to hang out one evening, and she says she can't because she has to do laundry. I look over and see I'm down to one clean shirt, and offer to drive her to one of the off campus laundrymats instead of having to wait forever for the couple of dorm washers.
This is before we are dating, and really just hanging out. When we get there she is so shy she makes me leave the laundrymat everytime she loads/ unloads anything with her underwear in it. We go to leave, I put my laundry baskets in first, load her 3 big bags on top of them and shut the trunk. Pull back up in front of her dorm and go to open the trunk. The key pops, then just spins and spins in the lock. It's raining/sleeting pretty hard, and she is NOT looking impressed.
As she storms into her dorm she tells me she has to study and I had better get her clothes to her soon. In shock I realize every tool i own is also locked in the trunk, so I head over to a buddies apartment and in the parking lot we remove the rear seat, and then manage to reach through two softball size holes in the bulkhead behind the seat, turn the clothes bags around, and start pulling all her clothes out, and stuffing it into trashbags. I'm freezing and laughing how she didn't want me to see her underwear, now I'm grabbing all of them. I eventually get the way cleared so I can use my boy scout lashing skills to tie a screwdriver onto the end of a sand wedge and pop the trunk.
I bring her her clothes back, and a few days later she tells me she is missing a pair of purple panties, and I need to find them. I figure they are long lost in the parking lot and never think about it again.
End of the semester, I drive her home and drop her off at her parents house. I've never met them before, but her dad comes out to meet me and we start talking about my car. He tells me he had one in college too and asks if he can take mine for a spin. I say sure, and hand him the keys.
He's a good 5 inches taller than me, so he sits down and reaches down to slide the seat back, and comes out with the purple panties wrapped around his pinkie.
His look was quite priceless. i stammered, thought about saying that they weren't his daughters, then figured that wouldn't really help the cause any and just drove around the block in total silence on a trip that seemed to take 18 years.
The REALLY bad part is I hadn't been anywhere CLOSE to her holy of holys at this point, but I didn't think he'd believe me.