Convert iMac into display for MBP, with option to switch back instantly

Hi.

I have two Apple computers. One is a MBP 2012 non-retina, and the other is an iMac mid-2011. (The MBP is my property, and the iMac is company property.)

I prefer using the iMac, but obviously all of my personal content and software is on the MBP. Therefore, is it possible to run the iMac as a second screen for the MBP?

If so, I would like the option to switch the iMac back to it's usual system. For example, I have days at work when I have a lot of down time. During these periods, I'd like to convert the iMac into a second screen for my MBP, simply for the comfort. But, when a work-related task comes up, I'd like to be able to immediately switch the iMac back into it's usual mode.

Also, I'd strongly prefer if files don't cross over at all. I don't want my files jumping onto my work computer, and I don't want work files jumping onto my computer.

Can this be done with the Thunderbolt cable or something?

Thanks!

According to this Apple document:

Target Display Mode: Frequently Asked Questions (FAQ)

...I believe the answer is yes.

- Nick

That's really awesome!

One thing that isn't clear is if it will act as a DUAL screen. Hopefully my MBP doesn't go dark when my iMac takes over. I don't have a Thunderbolt cable yet to try it out. Would anyone happen to know?

Your MBP will not go dark and yes, you do need a TB cable. You can buy a TB cable from monoprice.com for less than what you would have to pay Apple.