Guys, as I was new to this whole Mac OS X thing as well as Bluetooth (paired my Nokia 3650 with a WinXP laptop, but thats about it), I managed to get confused with the installation process.

Anyway, I figured that a step by step HOWTO would be useful for other newbies, so here goes:

1. Open Apple Menu -> System Preferences
2. Select Keyboard & Mouse, then the Bluetooth Tab
3. Click on Set Up New Device
4. Hit Continue
5. Choose Mouse, then Continue again
6. This is where I got confused - as the Logitech mouse didn't come with any documentation (well, maybe on the Windows driver CD, but hey, could I be bothered to look there. Don't think so), I didn't realise that you need to do something to the mouse to make it Discoverable.

On the MX900, flip it over, hit the Connect Mouse button towards the bottom end of the mouse (while the Mac is scanning for it), and Bob should be your uncle.

7. Set up Expose', it should now have a nice little section for configuring mice.

Hopefully this is of use to someone.

Sampsa

Definitely a helpful comment. Made this a very useful mouse!

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Mind the gap...