Add comma formatting to thousands, ten thousand, etc - i.e '£1,000,000'

Problem/Motivation

Thank you for this module..

Is there a way of formatting the numbers supplied in the range display?

I am looking to use this to display a range of money (with a £ prefix) starting at £50,000 and heading up to £1,000,000 and it would be good to 'break' the figures into thousand chunks to make it easier for the user (rather than £50000 - £10000000)

There might be an easy way to do this but I don't know it...