Your cat may show you affection by licking you. But some cat owners are uncomfortable licking their cats in response. Don't ask me why, but it's true.
Now those poor souls have a solution: the Licki Brush. It's a long, plastic, tongue-like object that fits inside your mouth. You use your head to brush it across your cat or the person sitting next to you on the bus. The soft bristles on the tongue groom and soothe the recipient of the licks. You can see a video demonstration here.