Cheapest I've seen this for. Around £15 most other places.
This cute little game lets you raise 3D virtual pets with the power of the PS3. Using PlayStation Eye, you can interact with your pet through gestures in realtime. Existing in Augmented Reality, your EyePet will be fully aware of people in the room and will interact with you and your friends in realtime -- it will even recognize items in your room and attempt to play with them! You can play with your EyePet (including tickling, playing chase games and teasing it to jump around,) customize its look and outfit, and even draw toys for it to play with!
* EyePet Reacts to Every Move and Command -- Place an object in front of the camera and EyePet will interact with it. Tickle EyePet by waving your fingers in front of the camera and he will laugh. Poke him, and he will jump. Roll a ball and EyePet will chase after it.
* Customize Your EyePet -- With over 250 unique collectibles you can customize your pet?look by styling his fur, changing his clothes, and giving him new toys.
* Graphics and Animation That Only the PS3 Can Deliver -- EyePet features Pixar-like fur technology and facial expressions. Watch EyePet change as he evolves over time.
* Create and Share With Friends -- Draw new toys and watch EyePet interact with them as they spring to life on-screen.