Here are all 21 of them, 14 of which start with the word Facebook: aboutfacebook.com, facebookbabes.com, facebookcheats.com, facebookclub.com, facebookdevelopment.com, facebookfest.com, facebookintegration.com, facebookjournal.com, facebookking.com, facebookland.com, facebooksafety.com, facebookstudio.com, facebookstuff.com, freefacebookapps.com, friendsonfacebook.com, fundraisingwithfacebook.com, joinusonfacebook.com, killfacebook.com, moneyfromfacebook.com, moneywithfacebook.com, and newfacebookapplication.com.

All the domains are listed for sale on Domain-market although none seem to list their current prices. If Facebook were to simply purchase all 21, it would probably not put any content on any of them and simply have them redirect to facebook.com.