Yahoo Tech Ticker anchor Sarah Lacy's BlackBerry has run out of power. And she wants the entire Internet to know about it ! Sadly, no one at Yahoo headquarters has responded to her passive-aggressively Twittered request. See, here's the thing about Twitter.You're not really sending the message to anyone specific, so everyone assumes someone else will respond. Twittering an urgent request in the hopes that someone will just happen to read it is sort of like expecting your personal assistant to just guess what you want, and do it. Oh, wait: Sarah Lacy does have a personal assistant . Why not just ask her to drive down from San Francisco with a charger? That seems easier.