Any cures for a cough?

The little man has been a bit under the weather recently. It came on just before the weekend, cancelling a visit to the grandparents and a rare Friday night out. At its worst, his temperature shot up which was the most worrying although Calpol and Nurofen did the trick and he was soon back from the firey brink. I must add at this point how relieved I was that I had paid that bit more and invested in one of those digital in-the-ear thermometers the doctors use rather than perservering with the forehead sticks that I never seemed to get the hang of. If you are in any doubt as to what to get, I recommend the Braun ThermoScan. Totally worth the extra pennies.
He has been left with a runny nose and a horrible cough that just heaves his little body constantly. He has always suffered from coughs, an inevitable after-product of any cold - and they go on for an age. Having dropped his daytime nap, he is back to having a two-hour sleep, as he is so exhausted by constantly coughing.
It can be so frustrating as there seems to be very little you can do about a cough.I am adminstering Calpol and cough medicine periodically and I have invested in some Manuka honey that an assistant at the local health shop said worked with her children although he doesn't seem to like the taste (and a drop of that ain't cheap I tell you). I am going to try sitting him in a steamy bathroom later this evening to see if that eases it. In the meantime, if anyone has any top tips on eleviating a bad cough, they would be most welcome.