As mc4man says, it's a symbolic link to the /usr/bin folder. If you look at the detailed listing:
You see that the symbolic link points to the current directory. If you're bored one day, you can try following it for a while. I don't think you'll find the end, thoughCode:$ ls -l X* -rwsr-sr-x 1 root root 10184 Mar 22 2012 X lrwxrwxrwx 1 root root 1 Jul 27 16:13 X11 -> .
At any rate, like others say, it's not worth messing with.