Warning::
These little creatures are habit forming even for the most focused of knitters.
They are fun, easy and thrive on lots of friends. You'll be convinced, quite easily, that there should be collections of them--Big collections--that promote gatherings of all types of critters. Cupcakes with eyes. Gnomes. Reindeer and mini cheeseburgers. They aren't about appearances as they all enjoy each others company and only require that you keep knitting more friends.
If you decide you need to knit some, keep in mind that I warned you.
Anna Hrachovec has a great site with everything you'll need to get started including the book that I used. If you are on Ravelry here's another great place to find her patterns.
Bet you can't make just one....