Smash hit

All change refers to shares that should not be badly affected by the credit squeeze, including supermarkets or tobacco firms. Uneconomic growth focuses on shares that are largely immune to currency movements and price controls, such as domestic food producers. Stewart expects more government spending to offset the economic downturn, so favours sectors such as surveillance and aerospace.

Finally, he likes large-scale construction groups because he predicts more spending on roads and telecoms, particularly in developing countries.

While these sweeping concepts help clarify investment decisions, they leave plenty of room for error: some road builders may not make profits for years.

You could instead go for companies paying good immediate returns, either in high dividends or shareholder perks.

Wills, a City stockbroker, has published a guide to investor discounts, from 10% off BA flights to 35% off Harry Potter books and cut-price Aga cookers.

If you are going to buy these items anyway, you might as well cash in. Just don’t be in a hurry to sell the shares, as most in the list are consumer firms that could be hard hit by the downturn.

Still, it can be fun to collect the bargains. Email perks@willsandco.com or call 020 7246 5454.

Freeze that price

The outrageous British Gas price rises last week have made millions of people even keener to buy themselves some certainty — and it is there to be had, though at a price. Energy will cost the average UK household nearly £30 a week, but if you move quickly you can put a ceiling on that.

British Gas says it won’t raise prices again this year, but you can extend that freeze until the end of next year if you shop around. Comparison site mform.co.uk has found that half its users have been asking about five-year fixed-rate mortgages, even though they are much dearer than variable-rate deals — and the betting is the next move on interest rates will be down.

Savings accounts are one area where you lose very little by fixing. The best one-year deal, just out, is ICICI’s at 7.2%. If you want to lock your money in for three years, though, you can still get 7.15% from Kaupthing Edge.

I suspect that competition for savings is about to heat up — Tesco is entering the banking market without having its hands tied by a now-defunct relationship with Royal Bank of Scotland. Understandably, however, it is staying away from mortgages.

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