Some things are best in small doses, including synth-laden dance-punk. That may be why Professor Murder sticks to EPs rather than full-length albums. Despite the critical acclaim that followed last year’s five-track debut, the New York City quartet has opted to give away Professor Murder on a Desert Island. You can find the opener, “Flex-It Formula,” along with the rest of the EP in upcoming months, at RCRDLBL.com, a new, ad-supported, label-approved blog looking to get into the free-music business. Sounds like a great idea, as long as those in charge remember that online ads are also best in small doses.