More commonly known as a 'setsquare', this pretentiously named weapon could do untold damage to the neck, thanks to its three mighty blades, or corners.

The Flexicurve - a bendy ruler used for drawing curves, but essentially a bar of rubber wrapped around a metal core. It doubled up as an amazingly effective cosh and thinking back, it reminds of that bit out of Lock, Stock... where that bloke gets beaten to death with a big, floppy rubber dildo.

The design and construction of Set squares is sublime. Not only are they perfect for causing untold injuries with their three points, but also have incredible aerodynamic properties. With a flick of the wrist, your average set square becomes a lethal shuriken, a deadly ninja throwing star.

For best effect, aim not at the eyes of children or animals, but at the cheapo polystyrene ceiling tiles on the roof and have competitions to see how many you can stick there before being caught.

Class 10X2's record was 14. The 15th one broke a tile, causing our own weapons to rain down upon us, along with asbestos dust and cobwebs.

These were also discovered to stick incredibly well into the ceiling of our technology classroom. Teachers would turn from writing on the board to see a forest of prongs dangly from the ceiling and a very innocent looking class.