answer:1. use monolingual:
http://monolingual.sourceforge.net/ to remove unwanted language localizations from your computer. i freed up a cool gigabyte and a half with this technique. 2. run through itunes and iphoto and kill duplicates. last time i tried that, i got back about 500 MB. 3. scour your apps folder for apps you never use… and delete them. 4. open a finder window at the top level of your hard drive, switch to list view, hit cmd-J (for “view options”) and turn “calculate all sizes on”. then sort the window by size. use the little disclosure triangles to open folders hierarchically in the same window, and you’ll see the largest files float to the top. delete anything you know you don’t need. this is much more productive than it seems. time machine is awesome, but it backs up by taking a complete snapshot of your hard drive… run a time machine backup a 3pm, then erase your hard drive at 3:15, then install a new copy of OSX at 3:30, then run a restore from time machine at 3:45… and at 4pm, your computer will be in identical condition to how it was an hour before. if you haven’t run time machine yet, the best thing to do is to clean up as much as you can, and then run time machine so you’ll be starting fresh.