Today’s featured promo on MacUpdate offers PackRat for US$14.95 (40% off, retail $24.95). “PackRat is a desktop client for 37signals Backpack Web application. You can download your Backpack data and use it offline. View it, make changes, create new pages, etc.. When you’re online PackRat automatically sends your changes up to Backpack keeping everything in sync.” PackRat requires Mac OS X 10.4 or later.