Daniel B - Rm 17 - made this amazing Hydraulic Claw for his Passion Project. Have a look at this video of him in action. 

I designed this hydraulic claw to pick things up. I found a model on google and copied it. It took me three goes to get it right and at one point I thought it was just too hard, however I persisted and got it to work. The different coloured water represents a different movement, like up, down, across, etc.