A related trick is to put a few drops of (olive, or other cooking) oil in your ear canal. Let it sit for 5 minutes. Repeat on the other side, and do this for 3 days in a row. This softens up the hard wax in there. Then flush out with a syringe if you want. Obviously don't do either if you have a perforated ear drum.
Yep, a few days of olive oil is generally recommended by GPs... I used to do this but now I self treat I don't really bother. But I guess it I'd have even more success if I did.