Last year I met a homeless Vietnam War veteran on the street. We chatted for a minute and he showed me his veterans ID so we could laugh at his picture because he found it amusing.
He was very hungry, so I bought him a large cheese pizza from across the street because I had a little extra cash on me. He had no idea about it, and the surprise was the best part!
It made me feel good to see him happy and at least fed well for the next couple days. It feels nice to help people out, especially veterans who have nowhere to turn but the streets.