The secret ingredient in all of those amazing cleaning products 'with a fresh citrus smell' is orange oil - it is found in small pores in the skin of the orange and is the stuff that tends to get you in the eye when you sink your thumb into a clementine.
As a cleaning product pure orange oil is awesome, removing sticky label goo, grease and dirt. You can also add a few drops to tung or linseed oil to give them a pleasantly orangey aroma.
