I'm currently using Ubuntu 13.04, elementaryos, and Windows 8. I would also like to install Backtrack for rare use. But I'm already out of my partition limit. So is it possible to combine two partitions and install all the Linux distros in that single partition with a shared swap?
For this, lubi is your friend.
Lubi is used to install any other Linux OS in the same partition as that of Linux. It means, if you are out of partition or you do not want to create an extra partition for any reason, then you can install the Linux onto same partition.
I have used similar technology for dual booting into same partition. I used the wubi. It's almost same, only difference is that, base OS is Window.
I had installed my own custom OS using WUBI.