I currently have Windows 8 installed via Bootcamp 4(?) via Mountain Lion.
I'd like to also install Windows 7.
Is there a way to do multiple bootcamp's - what is the best way to go about this?
Are you aware that you can boot a full operating system, nativeley, from within a VHD (virtual hard disk)?
This is fully supported by Microsoft, and allows you to reboot any Windows 7 or 8 machine using the VHD file as though it was your boot disk. Microsoft encourages this method for using their trial downloads - meaning you can now reboot and try out Windows Server 2012 or any other recent OS at native speeds, not emulated.
Here's a tutorial on building a Windows 7 bootable VHD file of your own: http://technet.microsoft.com/en-us/windows/windows-7-vhd-boot-demonstration.aspx
I recommend that you use either Parallels or VM Fusion for adding windows 7 to your Mac. OS Lion only allows 3 partitions, which Boot Camp use along with Mac OS!
By using Parallels (my recommendation) you can add Windows 7, which will work ALONG WITH YOUR Mac. I.e. drag 'n' Drop. copy/paste, etc.,!
With Boot Camp, you can only use EITHER Mac OS OR WINDOWS!
Can you define your needs a bit better? Why do you need 7 & 8? Can you get away with running 7 as a virtual machine in? Windows offers Virtual PC as a free virtualization solution.
Here is what I would try to do: