I played this game once a long time ago. Downloaded it to my phone. It's called 'Fruit Ninja' and it's just addictive. Just like watching this guy slice lemons in real life.

I am always amazed at the skill of someone that has been doing something for a very long time. This guy works at a lemonade stand or something. He cuts these lemons so fast, doing the work of 5 people all by himself!