What doesn't take much of your time, but can help turn a junk yard into a park or a derelict building into a community centre?
The answer is volunteering - and last year more than 20 million of you spent time doing it, according to the Home Office Citizenship Survey 2003-4.
Starting on Wednesday, this year's Volunteers' Week aims to recruit more volunteers, with a focus on employee volunteering and young people.
More and more people are taking time out to put something back
The annual event, organised by a group of volunteers' organisations, is held across the country to recognise and reward voluntary work.
To coincide, we asked seven volunteers to tell us their stories - from a man who saves toads from being squashed to a patrol of street pastors who spend time sharing pints with troubled souls.
Read their stories below and find out why they turned their passions into a community pastime.
FIGHTING THE ILLEGAL HORSE TRADE
Georgina Dale is a horse watcher. She keeps tabs on the shady world of equine crime to recover stolen horses and equipment.
As a volunteer co-ordinator for Devon Horsewatch, she scans horse markets for missing animals and liaises with the police.
The expert eye of a horse lover makes the difference in her work, says Georgina.
"If you're horsy you can see two brown horses side-by-side and tell them apart."
VICTIMS OF SEX TRAFFICKING
Jo Smith left her career as a teacher to help women abused by people traffickers and forced into prostitution in London.
Through her work with women's support group the Poppy Project, she helps them get out of the sex trade, get counselling and find work.
"Support work can be quite draining, but I never find it overwhelming because this is such a positive project," Jo says.
RIVER CLEAN UP
Depressed by regular sightings of sofas, fridges, cookers and even a car in his local river, Chris Scott from Grimsby set up the Friends of the River Freshney.
Together, Chris and other volunteers have transformed the area through regular clean-ups.
He is also trying to change attitudes towards local wildlife conservation.
"Education is the key," says Chris. "We want to raise awareness of how children's behaviour can affect the environment.
"Our marshes are gorgeous. They're like something out of Lord of the Rings when the sun reflects off the water. They have the potential to be the jewel in the crown of Grimsby. "
They patrol the streets of Birmingham late at night in uniform. But they're pastors not policemen, and their only job is to listen to the community.
Working in the city's Aston district, an area suffering from high levels of crime and social deprivation, these volunteers offer a listening ear to people's thoughts or problems, and are hoping improve dialogue between different communities.
Pastor Sylvia Josephs says: "We've never had any bad reactions, abuse or violence. People tell us they're happy to see us on the streets. They feel safe."
What do an oil rig worker, a farmer and a steam train guard have in common? They are all volunteer firefighters in a North Yorkshire village.
Mike Drewery leads a crew who are called out to tackle anything, from blazing cars to wayward donkeys.
In the day he works on the steam trains on the North Yorkshire Moors Railway - which can start fires alongside the tracks.
"One side of what I do causes fires - the other side puts them out."
It looked like a ghetto - but it was only a park in Hounslow, London.
When Jody Suden moved from the US to the area, she rounded up her neighbours, cleared up the broken glass and litter and began planting.
"Even though the US has a real history of local activism and a can-do attitude, I had never thought of myself as that sort of American", she says.
LIFE AS A TOAD WARDEN
When night falls, Andrew Town stalks toads on lonely country roads.
He's a volunteer toad warden and he helps toads cross roads safely on their way to breeding grounds.
The common toad is a seriously declining species. If Andrew wasn't out patrolling roads at night with a bucket and a warning sign for drivers, many more would be squashed under car wheels.
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