With the looming prospect of having to build ios apps around the corner but not having $2,799 in my pocket to be able to buy one of these, I decided I wouldn't mind coughing up the $19.99 to buy Mountain Lion. I knew already that its possible to find ready made copies of Mountain Lion that can be installed into virtualbox but I wanted to feel that I took the high road for a change and install it from an original, purhcased version. I couldnt find an existing guide for this so I figured out a few of the small parts in between other guides and here is the result. For the record, I am working on ubuntu and this guide will probably need adapting to do the same on windows.
I am not going to copy paste the hard work of tonymacx86.com so to start with find someone who has Mac OS X Snow Leooard 10.6.6 or later installed and then follow this guide to the end of step 2.
If you read the line above properly you should now have a nice bootable OS X usb install stick. The problem is that the usb stick will not be recognised by virtualbox or hackboot so the next step is a very small workaround. Open up your favourite terminal and do the following:
:~$ vboxmanage internalcommands createrawvmdk -filename /home/scott/osxusb/output_usb.vmdk -rawdisk /dev/disk/by-id/usb-Kingston_DataTraveler_2.0_ABCDEFGHIJKLMNOP123456789-0\:0
Change the green bit to wherever you want (its a very small file so no worries) and the yellow bit should match your usb stick.
Once again, I am not going to plagiarise so open up this guide but be prepared to add one small point to the end of Step One (so 1.6). Step 1.6 is very simple and key to this guide. After adding the Hackboot 1 ISO, click on "Add hard disk" under IDE controller and choose existing disk. Browse to the output_usb.vmdk file that you created above and click OK. You can now proceed exactly as the lifehacker guide says except when you open Hackboot 1 for the first time you should see a USB option to use instead. Thats it!
Have fun with your nice new purchased version of Mountain Lion OS X.