I love WD 40

 WD 40 was invented by Norm Larson in1953 (WD-40, abbreviated from the phrase "Water Displacement, 40th formula", indicating it was the 40th formula the chemists tried before finding success)    Originally designed for the Atlas rocket, it has a huge host of other things it can do (including making a mini flamethrower DON'T TRY THIS AT HOME)
 Why do I love the stuff?  Well apart from all the normal jobs of loosening seized nuts and squeaky doors I just mended a torch with the stuff.... Yes a torch.   About 5 years ago I bought x2  4w torches from a well known supermarket I hate (Cough Tesco!) I was doing a fair bit of exploring tunnels at the time.  Well the batteries leaked in one and buggered up the tail cap switch, I've tried taking it to bits but it's sealed, I was going to just throw it away (I'm not short of a torch or two) but then I gave it a squirt of WD40, clicked the button a few times and blow me down with a feather! It worked fine.  Jobs a good-un!
 So well done WD 40 you might be the same age as me but your still useful...... unlike me!