A man wears a necklace made out of silver and gold minted into coins containing the private keys to 65 bitcoins.

A man who grows and sells his own marijuana accepts bitcoin as payment because the currency can't be easily traced.

A physical bitcoin along with a collection of silver.

A man setting up a new bitcoin mining rig.

A man uses the Mycelium app on his phone to demonstrate how he can use BIP38 encryption to further protect his bitcoin and feel safe carrying a paper wallet with a private key exposed.

This man invests in gold, silver, bitcoin and other alternative currencies because he likes the freedom from government regulation.

This man says that one of the safest places to store a bitcoin private key is in a "brain wallet." With a brain wallet, users remember a specific phrase that is used to generate their bitcoin information. That means nothing is stored online, on a computer or phone.

A bitcoin mining rig set up in the spare corner of an office. At the time the photograph was taken, the rig could mine about one bitcoin per month.

The license plate of an early adopter.

A hosting company that accepts bitcoin adds a new server at their data center.

People meet up to exchange cash for bitcoin.

Several bitcoin paper wallets are given away to encourage the adoption of the digital currency.