Excuse me for being a bit thick, but why do our toilets have U-bends? What purpose do they serve? Surely if the waste went down a straight pipe we'd need less than the standard 8 litres of water to flush it down?

I'm trying to save water at the moment, so does anyone have an answer for me?

The following letter of complaint to Ofcom was written by our friend Josie Wexler and is published here with her kind permission. It raises a plethora of objections to Channel 4's 8th March 2007 screening of The Great Global Warming Swindle by documentary-maker Martin Durkin.

I found it depressing watching. I hope Ofcom takes action against Channel 4 over this, for the reasons Josie articulates so well. However, I suspect the screening has already done its damage: it is now being cited triumphantly on the blogs of those in climate-change denial.