Hmm... I guess the most recent one would be making a bunch of CD's for a great-nephew I barely know. He likes a certain type of music, and I just thought a kid his age (12) might like to have someone send him a nice surprise for no reason at all. I guess, too, I often try to be helpful to people online. I pretty much don't do anything "big and impressive" - just small stuff for people like family members or other people in day-to-day life.
Sometimes I think, maybe, the term should be, "Random Attitudes of Kindness", rather than "acts". Acts are good but sometimes isolated. I think "attitudes" can be a good foundation for a pattern of acts. Maybe that thought just occurs to me because I know I seldom, if ever, do anything all that "big and impressive". :)