Here’s “Hot Cold” live on the Ethereum “Homestead” network.

“Hot Cold” calls back to Art & Language’s 1960s Conceptual Art involving abstract aesthetic properties. It looks (and is implemented to be) twice as complex as “Is Art“, but it’s still really only one bit of information.

You can run the user interface locally in a web browser with an Ethereum node such as geth. Once geth is running, the user interface can get the contract’s state from the blochchain and, if you have Ether for gas, modify it. If someone else changes the contract’s state, you’ll see this updated.

If you want to change the contract’s status without using the user interface, you can do so using the contract’s address and ABI in EtherWallet.

The address:


The ABI: