When I was in grad school, I was poorer than poor. Like, can't afford beans on toast kind of poor. So I was working (bad idea in a thesis based MA), and coming home on the bus late at night in a dodgy section of Glasgow late at night. So I'm on the bus, and I'm eating this apple, and this old guy starts chatting about apples and what ever, and I mentioned that it was pretty much all I had to eat that night. Then this young guy reaches into his bag and whips out this massive chocolate chip cookie and just gives it to me. We started chatting, and turns out that he was reading this book called Danny Wallace and his Karma Army (blog here
http://www.join-me.co.uk/) and that I was going to be his random act of kindness that day.
I told a friend about it later that night and turns out that he had read that same book, and he gave it to me to read. It was a really fun read and gave me some ideas.
Basically, he and his "followers" (it isn't a cult, I promise you) practice "Good Fridays Agreement". Every Friday, they do random acts of kindness. I read the book, and started doing it.
Sometimes it was little things, like leaving 20p pieces on the edge of the pay toilets in the train station, or sending uber positive feedback to companies about their employees. Other times it was a little more elaborate, like going to the coffee truck on the way to uni and giving them a couple of pounds and saying, "please give the next five people who ask for coffee a free one on me", or buying a bunch of food and trying to give it away within a certain distance (ok, I've got five apples and a pear to give away between Uni and Kelvingrove museum, GO!), I've paid the bus fare of the person behind me (a favorite because they'll usually come and talk to you afterwards) I've left random notes in places with happy greetings or cute pictures in them...
I really enjoyed it. It was fun to do these things and not see people's reactions to them. I mean, yeah it may not have changed someone's life, but perhaps it gave them a bright spot in an otherwise dark day, or just a surprise. We've got very little to give us awe or delight these days, and so if I can do that, even in a little way, I will.