Mac OS X Only: Freeware Mail.app add-on Mail.appetizer lets you read and delete email on the fly without having to open Mail’s main window every time a message arrives. What makes Mail.appetizer stand out from other notifiers is the customisation—you tell it whether to show headers, icons, quoted reply text and determine its size. Mail.appetizer is freeware, available in a seemingly bug-free beta for OS X 10.4 Leopard and a stable version for 10.3 Tiger. Thanks, dcharti!