http://www.flattiredecor.com/ , as I'm posting this via iPhone and I can't figure out to make it link right). I really like the way they look, I love that they are recycled and I love how holy shit tough they are. There is NO WORRYING about these being tough enough to take whatever you throw at them.
We sell these at work and I just find myself wanting to use them for every display and workshop I do.
For giving, fill one with a giant bag of lavender bath salt, a package of band aids, sunblock AND sunburn relief gel, some Aleve and tiger balm. A gardener will weap at this offering.
P.S. I wish they came in a WAY bigger size, though. But I can see how they are limited by, ya know, how big a tire is...