So, you want S-Off on your One X/L, or Droid DNA? Done and done. Thanks to a crafty new "hack" by jcase and beaups, S-Off can easily be yours. As always, however there are a few pre-requisites, as well as some caveats to be aware of.
Firstly, you must have working adb and fastboot. If you don't know what that is, a quick Google search can answer it, and tell you how to get it. Your device must also be rooted and have SuperCID, no exceptions. This is requisite.
Devs work hard on exploits like this, and they risk bricking their own devices (or those of testers) in order to make it happen.