Those folders tend to be the largest ones, and can easily be symbolically linked from your non-SSD drive. He recommends only moving some specific folders to the non-SSD drive, specifically Downloads, Movies, and Pictures (for some users, Music may also fit in that category). Matt Legend Gemmell rightly points out that while moving the entire /Users/ folder is straightforward, it may not be your best option. There are, of course, other ways to do it. If you want to move your entire /Users/ folder to another drive, or to a different partition on the same physical drive, Jon's instructions will work fine. I kid because I love, Jon) but his information is still relevant. This was the same approach my friend Jon Deal detailed in an article explaining how to Move Your Home Folder Off Your SSD Boot Drive in OS X way back in November 2009 (because he's a huuuuuge nerd. The magic begins with right-clicking or Control-clicking the user name in the Users preference pane, which allows you to access the Advanced Options that control where the home folder lives on your drive.
Macworld just discussed one method, using the built-in home folder path controls in System Preferences. Friedman wrote in to ask about setting up a Mac Pro with an SSD in the second optical drive, keeping the /Users folder on another drive he wasn't sure how to do it.
