Please don't read if you haven't watched "Everybody loves Hugo".
So, Desmond hit Locke with his car. Here is my theory.
1) Since Flocke tossed Desmond over the well, Desmond conscious jumped to the Alternate timeline. Making Desmond attempting to kill the Alternate Locke. (This is a bad theory)
a)IF Desmond were to kill Locke. His mind will jump to the Original Timeline, so Alternate Locke will try to fight for its own body in the Original timeline causing multiple personality.
Anywho, it's pretty obvious (no spoilers, just the top of my head) that ALT Locke is going to treated by Jack at the hospital, and will most likely fix his spine causing him to walk again.
What are your theories?