I have, occasionally, but I don’t carry that much cash around (and I don’t particularly want to deplete my finances). I’ve heard that homeless people just want some acknowledgement - they’re hurt being treated like non-people - but I’m ashamed when I don’t give them money. But I should probably work up the courage to talk to them. They might appreciate just that. Or carry a lot of one dollar bills with me - one dollar is a pretty paltry sum but it’s something and I can start a conversation.