I just-this-second discovered this here on Anthropologie.
You can buy a small bag of seedbombs. what's even better, just like the urban beautification project, you can select seedbombs per what region you are in so that you are not planting something possibly harmful for your area and you will have more chance of success.
I think they'd make fun gifts for those not talented in the gardening department as the "bombs" are supposed to feed the seeds in case they are thrown into poor soil.
At Anthropologie you can also get pet-friendly and herb seedbombs.