We’ve had an email from Bala:

Can an aftershave which is nearly 3 years old be used as a car freshner??

This sent me down two research routes: 1) do aftershaves/colognes/perfumes expire? and 2) how to make a car air freshener. In answer to the first question, general not: they might lose their top notes or the scent distort in other ways after around five years but otherwise the alcohol will preserve it pretty well, especially if the bottle is pretty full (so there has been less exposure to the air). Some might separate slightly but at three years old, it should be fine.

As for making the freshner, Planet Green suggests a dangly scrap fabric/scrap cardboard/fabric sandwich, but I worry about the suggestion to soak the fabric with the scent – I would have though a few spritzes, refreshed regularly, would probably suffice in a closed car (a little scent goes a long way!).

Anyone got any ideas for making other types of freshner?

Or any other ideas for reusing or recycling old aftershave/cologne?