Lately, the clash between discs and streams has escalated, with Hulu, Netflix on the XBox360, and the recent announcement that even Blockbuster will begin streaming video via its new Mediapoint set-top. Now even New York's Criterion Collection has begun streaming video at its redesigned Website — with a twist. View a film for one week for five bucks — and if you love it, get five bucks off the DVD or Blu-Ray.