As other posters have mentioned, you can download the Mist client and test things on the testnet. And you don't have to mine, you can get free testnet ethereum

As other posters have mentioned, you can download the Mist client and test things on the testnet. And you don't have to mine, you can get free testnet ethereum via the wei faucet: https://zerogox.com/ethereum/wei_faucet https://zerogox.com/ethereum/wei_faucet Gas prices to run code on ethereum are fractions of ethereum, so even a small amount will get you pretty far.