title: getting rid of ruby gems that won't die
body: <p>I've got a few ruby gems that won't go away.  </p>
  
  <p>I think it has to do with when I installed them.  Occasionally I have forgotten to use "sudo" before doing a gem install, which results in a write error and from what I can gather puts a copy of the gem in my user directory instead of somewhere it can run.  But gem uninstall doesn't work.  It continually shows up in 'gem list' but can't uninstall it from either gem uninstall, or sudo gem uninstall.  I tried directly deleting one gem after finding the path in my 'gem environment', but that still left the gem on the list.</p>
  
  <p>Also is it possible just to remove all gems and start from scratch?  These are driving me nuts.</p>
  
  <p>I'm running OS X.</p>