giving a bunch of flowers to the person who looks the least likely to get them (you could tell them that someone else just asked you to do it for them ---if you are into anonymous.)
My Alan once bought a bunch of roses and handed them around to the elderly ladies in a cafe , to much giggles and delight. (one woman French-kissed him!)
He also bought the rose from the restaurant vendor and gave it to the lady behind the bar, who was looking tired. (This was in Florence and when we came back to this restaurant we were treated like friends of the family by the whole staff! )
He added a gnome to several people's gnome collection (at dead of night)
If you are an angel lover like me, sometimes you can collect an overwhelming amount of gift angels.
I recycled them in the post to friends who were having a difficult time, with an anonymous card .
Or leave angels in public places with a card attached that reads something like "This angel is here to help you--yes you! Take it with you!"
Leave books in airports and cafes (oops to the airport---probably be blown up!) with little reviews you've written, inviting strangers to take and enjoy and pass on.)
Put postive sayings into library books (best sellers) or in phone boxes or public loos.
Nature abundance gifts--- flowers you've pressed to artistic friends. Dried flowers and grasses made into tiny bouquets tied with ribbon--left for strangers or nieghbours. Seed packets made up from your garden favourites. Make simple paper punnets and give spare plums etc.
Other quick arty gifts-- get an envelope pattern and use colourful magazine pages and double sided tape to create envelopes. Add a sticky white address label. Wrap some in ribbon. and give to people as mad as you (through the post?)
How about the 29 things I like about you---but the anonymous version? Leave it for a collegue to find or post it through a neighbours door. (More sneaking, I love it.)
---this wonderful artist and writer has some lovely ideas including "invite someone dangerous for tea" She loves friendships with older people because they have lived so much...ask someone from another generation some questions about life.
is a for quilters, knitters or crocheters to make blankets for sick or injured children. They get it anonymously, just knowing someone cared. Anecdotal evidence suggests it has a direct effect on the health of the recipients
If you teach high school, consider reintroducing gold stars or "very good work" stamps. I had a collection of these for the first years, which made them giggle, but after a while the sixth years (seniors in US) were fighting over who had the best stamp. It was a tangible reward for effort and it made everybody smile.