Energy (with a focus on GB)

In Britain a market of sorts has been created for which supplier you buy energy from, where in theory the customer has a choice who they purchase electricity & gas from. It is a scam really but still better to play market than ignore it. For a long time you were most likely pay less if you switched from your existing supplier as well as often getting better level of service. Also you have option to choose to choose a contract that ensures more of money you pay goes to environmentally friendly generation of electricity. But for many years it seemed the amount of renewable energy produced will be determined more by government policy than green consumer demand. Care needs to ensure additonality.

Before changing utility supplier check out what Martin Lewis has to say at Money Saving Expert. (but they do not get every thing right with energy such as Smart Meters)

There are various price comparison sites. Citizen's Advice and before that Customer Focus and Energy Watch directed the public to these and Citizens Advice may still provide a list of them.