I have recently helped a number of people set their Facebook accounts up so that they accept friend requests from people they may not know very well (or coworkers who they prefer to not divulge all their personal secrets to). Facebook doesn’t make it very easy, but once you know how to do this, you will be sad/angry no one told you about it before. (I’m looking at you, Mark Zuckerberg.)

Roll over “Friends” at the top of the screen
Click on “All Friends”
on the left, click “Make a new list”
Follow the prompts, make one called, say, “Coworkers” or “Exes”
Put anyone who currently falls into the new list category into it.

THEN:

Roll over “Settings” (top right)
Click on “Privacy”
Click on “Profile”

You should see the list of categories you can specify settings for.

Under, say, “Status Updates” click “Customize”
A box will pop up, with a section for “Except these people”
Start typing the name of your list (e.g. “Coworkers”).
It should autofill.

This will allow you to let everyone see something except for a list. (or an individual like your mom or whomever). The reverse is to make a list of people who can see things. Makes no difference to Facebook.