I liked this point of purchase iphone app for Carling lager from BMB.
Its a skill based game where players attempt to 'slide' a pint to their mate along the bar by tilting their mobile use the handset’s inbuilt 3 dimentional motion detection. A successful slide wins an iPint, which fills up the screen just like a real pint. You can then ‘drink’ the virtual pint.
hat-tip to @jamiec.
Sorry it looks like BMB have taken their link down.