"There's nothing quite so jolly, as a lolly you can BLOW!"
Who recalls these? They were, quite literally, small hardboiled lollipops on sticks that also functioned as whistles, so you could blow them to make a 'peeeep' sound as you sucked them. An ingenious idea that was launched around '79, though sadly short-lived; they had disappeared from the market by the mid-1980s. How they worked depended upon how succesfully they'd come out of the factory moulds- some disappointingly didn't work at all, others produced a magnificent tone in E flat that would've done credit to a professional standard recorder. Of course, their ability to function wore down as the lolly was slowly dissolved!
I was already about 10 when these things were launched, and a bit old to be as entertained by them as I might have been a few years earlier, but I well remember the TV advert. It was of a small circus with variously-dressed adults capering around in the ring, including a uniformed female ringmaster, all singing of the virtues of the sweetmeat whilst a man dressed as a steam train went along the child audience distributing the lollies to them. Classic!