The extension of the London congestion charge zone into areas in the west of the city has again thrown the spotlight onto road charging and pricing across the whole of the country.
Seven areas - Durham, the West Midlands, Greater Manchester, Tyne and Wear, Shrewsbury, Cambridgeshire and Bristol - were given government funding in 2005 to look at road charging.
But while many cities have considered schemes few are at the point of putting them into practice.
Manchester could have congestion charging on key routes into the city as early as 2012.
All the local authorities within the Greater Manchester area met at the end of January and agreed in principle to a charge on 15 roads.
After years of development and economic growth, Manchester can now suffer nightmarish rush-hour traffic.
The charge would cost less than London, but it is dependent on successful applications for grants to tackle public transport across the region.
Bristol, along with three other authorities - South Gloucestershire, Bath & North-East Somerset and North Somerset - are likely to be among the first places to take part in a national network of pilot schemes.
The council said in March last year that a questionnaire had showed support for a congestion scheme. Council leader Barbara Janke said: "We have to do something about congestion - and this is it."
Any scheme would be closely linked to big improvements in public transport.
A body representing local authorities and transport authorities from across the West Midlands has produced a green paper, Gridlock or Growth, which suggests some form of congestion charging as one of a number of options to tackle jams.
But no decision has yet been reached and the authorities believe any scheme would be dependent on major improvements in public transport and would not be in place before 2014.
In December 2003, the M6 toll road became Britain's first fee-paying motorway. The current cost for travelling down the road is £4 for cars and £8 for HGVs.
In February 2005, residents of Edinburgh voted overwhelmingly against a congestion charging scheme that would have seen drivers pay £2 to get into the city and face fines of £60 for not paying.
After residents voted 3-1 against the scheme, the council's leader described the scheme as "dead and buried".
But supporters have said Edinburgh will need to revisit the idea in years to come.
Scotland's other major city has also set its face against congestion charging.
The council says congestion charging is too crude a measure to fight traffic jams.
"It takes no account of the differential in terms of affordability for a businessman having his costs met by his firm and the family of four making a brief trip to the shops," a spokeswoman says.
Instead, the council is committed to controlling congestion using parking restrictions and improving public transport.
Durham has had its own mini-congestion charge since 2002, making it the country's first.
The scheme, which was intended to control traffic on one street in the heart of the historic cathedral city, has won a number of traffic management awards.
After receiving its grant from the Department of Transport, Cambridgeshire County Council launched a study to find a way of reducing congestion, which is due to report back this year.
Nothing has been ruled in our out, although the study will have considered both the road charging issue and the extended use of rising bollards to control access to roads.
TYNE AND WEAR
A project entitled People in Motion, part-funded by the DoT, is looking at "demand management" for traffic across the region, which is predicted to rise as car ownership and the regional economy grows.
It will not report back until at least January next year, and road charging is only one of seven issues being considered.
DERBY, LEICESTER AND NOTTINGHAM
The three east Midlands cities are engaged in a £1.8m project which will study traffic and consider the possibility of congestion charging.
In Derby, the Labour-led council has proposed congestion charging and also discussed introducing new driverless trains.
Congestion charging is being considered in Cardiff as well as in other areas of south Wales, but no definite decisions have been taken yet.
In 2000, then Northern Ireland minister for transport Gregory Campbell said toll charges were possible as a radical solution to fight congestion in Belfast. But no measure has been introduced.