Benefit from dollar rally
As forecasts for the direction of the UK and US economies change, the impact on the nations' currencies in recent weeks has been dramatic.
The dollar has enjoyed its longest successive run of daily gains against sterling in 37 years - helping it to surge 7% on the pound since mid-July.
But what are the implications, and potential benefits, on UK consumers' finances from the dollar's bull run?
The main impact of the strengthening dollar is on the spending power of tourists heading to the US on holiday.
Sterling was worth more than $2 just a month ago but it has since fallen as low as $1.85 amid growing expectations of a reduction in UK interest rates.
Analysts are now predicting that the pound, which hit a 15-year dollar high only last November, will see further falls in coming months.
Neil Mellor, at The Bank of New York Mellon, says an impact of the falling pound is that it raises the value of assets held by UK investors abroad.
This would include money invested in the American stock market.
Neil Mellor, currency strategist at The Bank of New York Mellon, says investors should be mindful of the impact of the strengthening dollar on UK equities.
"It will help certain stocks which are exporters to the US as they will increase volumes and also benefit from converting US income into sterling."
However, retailers which buy imported goods are likely to be hit as the cost of US goods increases.
Ken Dickson, currency investment director at Standard Life Investments, says the dollar is likely to gain on the euro and pound ahead of anticipated UK and euro rate cuts in 2008 and 2009.
He said: "If sterling is falling then it would pay to diversify a portfolio globally to add to performance.
"Irrespective of performance, currency changes could make holding US shares more attractive."
There are several ways in which small investors can speculate on currency movements, says Stephen Barber, head of research at stockbroker Self Trade.
They include covered warrants, a form of options contract which allows an investor to buy or sell currency at a specified future price and date.
He said: "Covered warrants are a very retail-friendly way of speculating on foreign currency movements."
Contracts for difference also offer exposure to currency, which allow investors to trade "on a margin", ie use a small stake to get big exposure.
However, such methods can see investors lose far more than their initial stake if the market goes against them.
Geoff Penrice, financial adviser at Bates Investment, said: "Currencies can be very volatile and there are many factors which can affect their value."
One advantage of using derivatives instruments such as covered warrants or CFDs is that they don't require large sums of initial investment.
Specialist foreign exchange trading accounts are available although the minimum deal size is typically far higher than for alternative methods.
A further option available to investors is spread betting, which also allows speculation on currency movements.