Copy a key with a Coke can
Attention cheapskates and locksmith apprentices, this key copying solution is stunningly simple.
We've really mulled over this one. As you can read in the comments below, people struggle with executing this successfully. But it can and will work. You just have to modify your key to fit your needs.
This trick works with certain light locks found on mailboxes or gym lockers. Most heavy duty deadbolts require an addendum. You will need to go beyond a single layer of aluminum.
To unlock a door or security lock, reinforce the handcrafted key copy with several duplicate layers of aluminum. Use a sharp Exacto knife rather than kitchen cutlery or scissors to ensure precise cloning.
Copying keys is just the beginning. Check out this list for more odd uses for an empty Coca Cola can.