My friend's SO left her with 3 kids and no money. She didn't have a job and she had $600 worth of bills due, I had extra money so I gave it to her. She said "I don't know if I'll ever be able to pay you back"
Well, her SO came back, he got an awesome job and she got into school. She got loans and pell.
She's never mentioned the money. Now I'm struggling and I can't even explain how much $600 would help right now!! :-/
Eta: I loaned her $100 in 2010, it took a year for her to give that back.