If you don't know about the program Monolingual, you might be as lame as I was 30 minutes ago.
This is one of the best ways to free up precious space on your wank machine.
It allows you to choose which languages to keep and which to ditch. I don't plan on ever using anything other than English. So I deleted all but English.
Mac allows you to change your whole computer and all its components into about 80 different languages which this Mac has a profile for.
This freed up over 3 gbs for me, the program is still running and continues to free up space.
The next best way that I have found to save space is to delete the preinstalled Printer Drivers.
You can choose to delete all or some. If you really need one later you can just install that driver at the time of need.
This gave me about 2 additional gigabytes.