I designed and built this arm for an engineering challenge at a NC State University engineering summer camp. The challenge was to build a mechanical arm that could grab a snickers bar and lift it up. My available resources were Popsicle sticks, scissors, hot glue, syringes, and plastic tubing.
Many laptops tend to run very hot, and as a result their tiny blower fans have to work hard to stop the computer from overheating. Simple ways of fixing this include taking some compressed air to the heatsink, or reapplying thermal paste. But this is a far more interesting solution.