Sharing a Bluetooth Keyboard and Mouse sequentially between two Macs

I work out of my house where I have two computers: a mid-2010 Macbook Pro (for my day job) and a mid-2010 iMac (personal). During the workday, my iMac acts as a second display for my Macbook Pro via Mini Displayport.

Currently, I use a USB keyboard and mouse for my work computer and a Bluetooth keyboard and Magic Mouse + Magic Trackpad for use with my personal computer. I'd like to get rid of the wired keyboard and mouse and just use the Bluetooth stuff for both machines (but never simultaneously).

Is it possible to easily share the single set of input devices without having to repeatedly break and reestablish the pairing of the input device to the correct computer? I'm not opposed to buying some type of additional hardware to accomplish this, provided it's not prohibitively costly or cumbersome to use or configure.

It's not clear to me how I would tell the MacBook Pro to leave the devices alone so the iMac can have them for the evening. I want to avoid de-pairing and re-pairing the devices each time I want to shift them back or forth.

Basically is there software or hardware that works as a Bluetooth KVM switch?

The trouble is with the devices, the Apple mouse and the keyboard in your case. They don't pair with more than one BlueTooth host at a time. You need a BlueTooth host that's "central" to both Macs if you want to use them.

You can find KVM switches that have BlueTooth host receivers in them. For example, the Zonet KVM3322W (dead link) worked over USB and provided BlueTooth receiver capabilities. I cannot attest to how well that would work. Presumably you'd pair the keyboard and mouse with the BlueTooth receiver in the KVM instead of in either Mac and then using the keyboard shortcuts, switch between control of the Macs who are connected to the KVM via USB. How the Macs would respond to the BlueTooth receiver in the KVM coming and going as you switched between them is unclear to me. Could be they handle it just fine.

The other option is to seek out BlueTooth accessories that allow themselves to be paired with more than one host. And then switch between those hosts from hardware keys on them. For example, this keyboard+trackpad combo from IOGear supports switching between 6 BlueTooth hosts. So you'd pair it with both Macs and the use the keyboard switches to decide which one you were talking to at any point in time. That, to me, seems like the more reliable approach. Of course: now you're stuck using IOGear's keyboard instead of the Apple peripherals.

I, too, was looking for an answer to this very question. Here is the solution that I came up with:

1. Go to System Preferences -> Bluetooth
2. Click 'Advanced'
3. Make sure that 'Allow Bluetooth devices to wake this computer' is unchecked
4. Click 'OK'

Now, when I want to switch from my main computer to my MacBook Pro, I put the main computer to sleep and wake up the second one. The bluetooth keyboard and mouse both switch over to the laptop and away I go. When I want to return to the main computer, I put the laptop to sleep and wake the Mac Mini using its power button.