Software is available that allows you to run Linux and Windows within a 'virtual machine' on a Mac OSX system. Apple's licensing forbids using Mac OSX on 'virtual machines' running under Windows or Linux, however.
Still now we can not use the Linux emulator drive for Mac OS because software of one OS is not support to another. Those types of software are developing now.
You will not find a full fledged Linux emulator for Macs, but there are many different Linux distributions, and probably you will find one that gives you functionality without a full installation.