You may be interested to know that I converted my 2003 Charade to run on LPG last July (2009). It was done by a company called Autogas Solutions. It cost £1000, but now I'm using LPG at 53.9 p/l instead of petrol at 109.9 p/l (Morrisons prices). The car runs perfectly well - no problems other than a gas pipe rattling against the car's bulkhead, which I fixed myself. It does about 40mpg on LPG instead of the 50mpg I get on petrol (round figures) so that has to be factored into the equation. I calculate the payback will take me about two and a half years. An added benefit is that tax goes down to £15 per year and I think you are exempt from London's congestion charge, though I'm not too sure about that. The downside is that the 40 litre tank is fitted in the spare wheel well, so I have to carry a can of squirty stuff in case I have a puncture.