A chest of drawers in my son's room has 2 drawers that "fall out" or tip down when opened. Turns out the problem is the little plastic things that keep the drawer from falling out when it's pulled open have broken. What are those things called and where can I find replacements?
Ahhhh! Thank you! I am glad to know what they are called finally.

Drawer stops such as
http://www.rockler.com/product.cfm?page=206&filter=drawer%20stop
or
http://www.rockler.com/product.cfm?page=1627&filter=drawer%20stop

You might also find them at Lowe's, who have a pretty extensive selection of drawer parts, or your local hardware store.