Tim Warriner

Removing the Mystery of Euler's Formula [PDF]:
An explanation of Euler's Formula (e^ix = cos x + i sin x). [Mirrored from my temporary website]

Storing messages in playing cards:
How to encode and encrypt binary data into a deck of 52 playing cards.

Things from years ago:

How to remember which cards have been dealt from a pack of cards: here

Dismantling a Chubb Manifoil combination lock: here