I am one of these people and still have not found a working solution. I already installed Lion, but now I want to do a clean install instead from a USB stick, and cannot find a way to re-download Lion, which is necessary to get access to the .dmg file. Holding the option key when I click the Purchases tab in the App Store does not work. Holding the option key when I click OS X Lion in the Purchases tab brings me to Lion's page with "$29.99" as the install button rather than "Installed", but when I click it, it tells me I already have a newer version of this app installed. Please help the many of us that made this... "mistake"? Edit: I finally figured it out. You need to quit the App Store, reopen it, and without doing anything else, hold the option key and click Purchases. Lion should then be downloadable again for free.