In these heady Web 2.0 days — or have we already moved on to 3.0? — it's not unusual for a blog to become a brand name almost overnight. It's also not surprising that some of the best-loved music sites have extended their reach beyond the virtual world. Take Daytrotter.com, the Rock Island, Illinois, hub that records and posts free live tracks from touring musicians. The site is sponsoring this current tour by Ezra Furman & the Harpoons, a Boston-founded combo that pairs street-skiffle rhythms with garage-rock bravado. Furman attacks the microphone with a seething smirk, as if the Violent Femmes' Gordon Gano put on Iggy Pop's too-tight trousers by mistake, and his Harpoons goad him on with the right amount of dirty twang and power-pop stickiness.