Diggy is an open-source playground that runs practical and recreational programming languages. Simply put, you can Ruby or Python in the browser.
Click a link to use Diggy or give it a try in the code editor below. It creates a new workspace everytime you load a page. No accounts required.
Your code is executed in a sandboxed environment, and the results are sent back to the browser. Since everything runs in a protected sandbox you cannot access network interfaces or (hopefully!) break anything.
Ultimatelly, have fun!