If you'd like to have caramel handy for baking projects or just eating with a spoon you can make it easily by boiling a closed can of condensed milk in water for two hours.
Flickr user Pinot Dina figured out if you bring a pot of water to boil then immerse a can of sweetened condensed milk on its side. You'll need to simmer the can for two hours, adding extra water as needed so that the can is always covered in water. When the time is up, remove the can and let it cool before you open it up, lest hot caramel splatter attacks ensue.
Give it a try next time you need some caramel.