Aloe vera plants grow well in crowded conditions, and they actually seem to prefer it that way. You can plant a couple of aloe vera plants in the same pot together, and even let them grow to the point that their roots take up to 2/3 of the pot.  And living in tight quarters will stimulate your aloe to start sprouting pups (smaller offshoots) around its base- which means you get a brand new aloe plant!