It is possible that you use the Bluetooth of your Mac to send files to the mobile phone, and in that case this trick can help you a lot, since it speeds up this transition quite a bit.
The trick is as simple as hovering over the file we want to send and pressing the Shift + Cmd + B key combination. So far so good in Leopard.
But if we have Snow Leopard, what we have to do is activate the shortcut, which comes 'off'. And for this we have to go to System Preferences> Keyboard> Keyboard shortcuts> Services. And there we activate it.
Source | Apple weblog