You have to sign up as an official Microsoft-sanctioned hardware OEM. Usually you have to pay a dominatrix to put you through a process like that, so it could be considered a relative bargain.

Technically it's not kosher to use the license for general work around the home/office, natch. The IoT licenses are supposed to be used only for developing, testing and selling hardware (and selling it directly to end users only, at that.) But at least the license exists.