Film -- A Gathering of Coens (y'know, like the brothers) at the Brattle begins with screenings of No Country For Old Men. 40 Brattle Street, various showings, $7.50 matinee, $9.50 evening. Dancing With Ourselves -- We've never much liked electronic music, so imagine our delight at discovering the silent rave. People will gather to dance to their own individual drummer, or flautist, or pianist, or whatever imaginary music propels them. No word on whether pacifiers......