If Gmail was enough like a desktop app for you, here’s another feature that’s been associated with desktop apps – drag and drop support. No more hunting around with the Open File dialog, just drag and drop the attachments and you’re good to go…
When you drag files into the browser window, a “Drop files here” pane appears bellow the “To:” field. After you drop the file (it works with multiple files but not with folders), they are uploaded as usual.
For now, this feature works only on Firefox 3.6 and Chrome – there’s no support for Opera or IE.