CalculatorsCalculatorsCalculator.com 
Lots of different calculators.
Megaconverter
Converts anything to anything.
MoneyExtra Calculators
Handy online tools to help you calculate your mortgage, tax and insurance costs.
Digita Tax Calculators
A range of tax calculators.
VAT Calculator
Use this tool from Digita to calculate the VAT contained within a total amount, or the VAT charged on a net amount.
Car Running Costs
How much does it cost to run your car? Useful interactive guide from the AA. For fleet vehicles, FleetNewsNet's running costs
database allows you to search for benchmark pence per mile costs across thousands of popular fleet vehicles.
BPPG Interest Calculator
A quick and easy way to calculate the amount of interest you are entitled to charge on outstanding debts.