Right Meta Key??

I've recently installed Ubuntu server, and am trying to learn the command line. I've noticed that only the left-alt button works for keyboard shortcuts on the line. My understanding is that the right-alt is reserved for other functions. A quick google search revealed that pressing both the right-alt key and right-windows worked as the meta-key. Is there a way to map the right-alt key to the left, or more preferably, the right windows-key? I am new to Linux, and thought I would challenge myself by not installing a GUI. I tried installing xserver-utils, as I read somewhere that key mapping can be accomplished using xmodmap. I am, however, unaware of how I do this from the command line.

You need to start by using the showkey command to find out the keycode for the alt-gr key. Then you can define this keycode as meta. This HOWTO page gives some examples of changing modifier keys.