Comment by bybjorn

The license is called "Developer license" which I at least associate with multiple use, and I don't see them specifically mention "single use only" (although I see that the text can be interpreted that way) .. http://designmodo.com/startup-license/

EDIT: got a reply from them on twitter: https://twitter.com/Designmodo/status/412867217118605313

You were right: "one license - one project."