They were little knitted pink figures from outer space that were big in the 1970's and all speech noises were made with a swannee whistle. They fished for space junk, ate soup from the soup dragon and lived in tunnels under dustbin lids.
A while ago I found a set of Clangers ink stamps and made this ATC using it.
Apparently all the dialogue was scripted, even though it was spoken on a swannee whistle. The narration was by the incomparable Oliver Postgate: THE voice of the 70's for a generation of children, myself included. In fact I believe he was the creator of ALL the Clanger-y stuff. Genius!
Sample and get hooked at: http://www.youtube.com/watch?v=sCcD0aqUgCo