I saw my first £1 Litre of diesel this week. 100.9p at the Hendon Way BP. I suspect they have been trying to delay going to triple digit pence, but had to give in. I filled up for a penny less elsewhere. I could have got cheaper if I could have waited, but I was getting very low on fuel. I don't generally drive further for cheaper fuel, but usually hang on if I know it's cheaper further along my route.
While I'm on the subject of prices, why do we have to have .9 or .99 prices everywhere? Are people really fooled into thinking it's so much cheaper? For a TV to cost £499.99 rather than £500 is silly, but for a magazine to cost £3.99 is a pain as you just end up with loads of pennies if you pay cash. If it's less than 1% of the price I just don't care about the odd penny. With fuel you are dealing with tenths of a penny. I expect the argument will be that nobody wants to be first to make the change.
The fact that everything is priced at these artificial numbers shows how contrived pricing is. Prices are rounded up to whatever it is though the market will bear. Some internet retailers are going against this and pricing at the minimum they can sustain as they know people are using comparison sites to find the lowest possible price. I buy most major items on-line these days in order to save a few quid and to avoid having to trail around all the shops.