It was fun finding Facebook user ID (uid). I need to search everywhere for this. It is my user Id but it is not available on Facebook profile.
Trick I got is, post a comment on any Facebook page and mouse over your name in your post comment. You will see a link at the bottom of Browser in status Bar. If it is disabled then copy the link using right click and got it. It is the number after profile.php?id=?.
I have posted my sample comment here. You can join my Facebook page and try there as well. The profile Id (user id) is not visible when you post on your own page.