1111 is a common phenomenon, it happened to me about a year ago. Though my experiences were more intense than merely seeing the number on a clock. I was literally going insane, suffering from psychosis. I was reading stuff on the internet about starchildren and that they were awakening through digital code. I was lead to this site that talked about the number 1111 and at that point, just as I looked at the number I felt something, not only inside of me, but outside as well, trigger. At that point I started to see the number 1111 all around me, and I mean everywhere.
That was the point at which something happened to me. I can't explain what, but it was very spiritual. It was some sort of initiation thing.
I know a lot of people who have been through this same process. All of them from another forum that I used to frequent (though is closed down now.).
I believe that the same thing is happening to you guys.

Here's a site that explains it well:

http://www.crystalinks.com/11.11.html

All of these 4 or 3 digit numbers that you guys are seeing are linked synchronously with your spiritual evolution. It may take time but something will happen to you that involves these numbers. A spirtual enlightenment of some kind.
I still can't explain what happened to me, but at the time I was receiving al ot of messages from God. And the world around me.

Hope this helps,
Enlightener.