I've actually got one 24" iMac at home that I think I still have Xcode 3.2.6 and Mac OS 10.6.8 on for ye olde pre-storyboard projects.
I can strip that OS down and test putting it into a VM in VMWare Fusion for giggles - just to see if it can actually work.
Since you're at MIT, I'm in the area and if I get something to work, (I don't see how it can't work) I'll be glad to help you get to a working solution.
Putting different versions of the Mac OS and Xcode on VMs has been a lifesaver for me, since I can test out new things without messing with my currently working setup. When something new comes out, all I do is…
Leave my currently working OS.
Duplicate a working VM and upgrade the OS, install the latest version of Xcode, whatever I want to test out.
Start monkeying around in the new VM without destabilizing my current workflow.
On modern Macs (anything from 2011 'till current), with RAM and a fast drive, it's a no brainer for me. I've got 5 little 80 GB VMs currently and if I need to switch back to a working setup from 2 years ago, I just open it up.
I've actually used that approach to test on multiple simulators when my iPad broke. Think I've had 3 VMs and the current OS open at the same time on a 2011 MBP 17 with an SSD and 16 GB of RAM.
Honestly, if you've got the 50 bucks to spend on Fusion, I don't know why you wouldn't do it.
In any case, If you want to see if I have a VM up and running with Xcode 3.2.8 and Mac OS 10.6.8, email me offlist later tonight.
Cheers.