Simple Air Freshener

Sometimes you have smells in the home you want to mask quickly. I'm not talking of smells due to unhygienic circumstances or stale air but am thinking more of cooking smells or fish smells etc.
I have found that Sticking a piece of cotton  material on the radiator with a piece of low adhesive paper maskingtape and then dropping a drop of essential oil or perfume on it helps a great deal.
This only works it the heating is on of course. 
During summer or in warm countries you could lay the piece of material in the sun on the windowsill.