Uncomplex has tweaked Mailplane, its WebKit wrapper for Gmail, with a handful of minor fixes and improvements. Picture optimization in outgoing messages can now be controlled via AppleScript, dragged messages now disappear as expected, dragging images onto Mailplane's icon now optimizes pictures reliably, and keyboard shortcut functionality broken by Gmail changes has been restored ($24.95 new, free update, 19.9 MB)
New Documents in Snow Leopard's TextEdit
In the Snow Leopard version of TextEdit, you can now create a new document by Control-clicking TextEdit's Dock icon (when it's running), and choosing New Document from the pop-up menu. This isn't a major feature, of course, since you can also just press Command-N while in TextEdit, but consider Control-clicking other applications' Dock icons to see what functions they might make available.