Benny, I LOVE Ever Decreasing Circles!! I have the boxsett on DVD. It's very very cleverly written.
I believe the Bryce's (Anne and Martin) had a Goblin Housemaid hardbag and then a Hitachi CV50D (as shown on the kitchen table in the episode you linked to).
Here is a quick video of the Bissel Spinfoamer in action. This was the electric model with rotating bristles to sweep the foam through the carpet pile. Not very effective, but does ok. Same method that a Kirby uses.
[MEDIA=youtube]zpSFtPgDZZU[/MEDIA]
