A Vista-esque feature of OS X Leopard is that it tags web downloads (not just from Safari) as such and then warns you about running downloaded apps or scripts. Archived (e.g. zipped) files inherit the tag from their tagged container. This is an annoyance to power users. Luckily, being a power user, I can do something about it. ;) Stick Unquarantine.scpt in ~/Library/Scripts/Folder Action Scripts.