The Daily Telegraph has published details of many MPs' expenses claims over the past four years.
Amid the negative headlines generated by its revelations, there remain MPs from outside London who, in the year to April 2008, claimed none or only a fraction of the £24,000 second homes allowance designed to cover the costs of them having to be in the capital on parliamentary business. Here are some of them:
Martin Salter, Celia Barlow and Geoffrey Robinson are the three Labour MPs from constituencies outside London not to have claimed a penny in second homes allowance last year.
Martin Salter is happy commuting from Reading to London
Ms Barlow, elected MP for Hove in 2005, has a second home in London but does not accept any public funding for it through a matter of "personal choice".
Mr Salter, who is standing down as MP for Reading West at the next election, says he commutes to and from Reading most days and therefore does not need a second home.
Former minister Mr Robinson is a multi-millionaire following a successful business career.
Other Labour MPs who chose to claim only a fraction of the maximum £23,083 allowance permitted in 2007-8 include:
Kelvin Hopkins: (Luton North: £1,242)
Fiona McTaggart: (Slough: £3,392)
Alan Williams: (Swansea West: £5,221)
Jon Trickett: (Hemsworth: £6,141)
Ed Miliband: (Doncaster North: £7,670)
A handful of Conservative MPs - some within commuting distance of London - did not claim any second home allowance last year.
Philip Dunne has a flat in London but does not charge the taxpayer for it
Adam Afriyie: (Windsor)
Richard Benyon: (Newbury)
Philip Dunne: (Ludlow)
Anne Milton: (Guildford)
Rob Wilson: (Reading East).
As well as not claiming a second home allowance, Mr Afriyie - elected in 2005 - was not reimbursed for any travel costs.
Mr Dunne owns a flat in London but says he believes claiming for it is not "the right thing to do".
Ms Milton says she does not need a second allowance as she lives in Guildford - about 40 minutes away by train.
Ann Widdecombe, MP for Maidstone and The Weald, claimed just £858 in second home allowances last year and says MPs who have abused the system should stand down.
LIB DEM MPS
David Howarth says changed sitting hours allow more MPs to commute
David Howarth, MP for Cambridge, is alone among Lib Dem MPs outside greater London in not claiming for a second homes allowance last year.
He says he prefers to travel to and from Cambridge every day because it "keeps him in touch" with his family and his constituents.
He says the second home allowance should only be used for paying for hotel accommodation or rental property.
The Lib Dems also point out that none of their seven MPs from outer London, who were entitled to claim the second home allowance in full, did so as a matter of party policy. The seven are Vince Cable, Ed Davey, Susan Kramer, Sarah Teather, Tom Brake, Paul Burstow and Lynne Featherstone.