Give blood
A few months ago a colleague sent around a note asking if anyone wanted to go with her when she donated blood and I realised I hadn't given blood in such a long time.
It's such a simple thing you can do every few months and there's no doubt in my mind it can mean life or death for someone. I'd like to say I pray while I'm laying there, but I don't...but I might start, actually. So unless you are extremely squeamish around needles... or a vampire... I'd say take a jab at it.
Suggested by Naomi Rose
