Stickershift is a series of high-quality automotive enthusiast iMessage stickers made by Tapbots designer (and big-time car guy) Mark Jardine, with development by fellow Tapbots co-founder Paul Haddad. They put together a nice little video showing the stickers in action:

The pack includes 12 free stickers, with another 63 that can be unlocked (along with any future stickers) for just $2. Download it for free from the iMessage App Store.