Change keyboard layouts if you have ergo problems, like I did. Don't change for speed; you won't gain any.<p>If you are finding that your keyboard is slowing you down while you code, though, consider changing your tools -- get a new programming language, or a new IDE. A concise language like Haskell requires very little typing, but you end up thinking about each line for a long time. If you're using Java with a plain text editor, consider switching to Eclipse; I find that Eclipse ends up entering about a third of the code that I author.