Right - Mary didn't bounce to Bethlehem on a knackered donkey and birth the Baby Jesus in a filthy stable just so you can stuff yourself senseless for a day.

In fact, if the thought of shovelling massive amounts of dead bird into your gob, followed by lying in a food-induced coma, glazy-eyed, trying not to strangle your sister-in-law leaves you feeling unfulfilled and a little empty, why not volunteer this Christmas?

"A lot of people are reacting against the commercialism of Christmas," says Jennie Smith, volunteer manager for homeless charity Crisis. "They want to do something other than sit around and stuff their faces. The nice thing about volunteering at Christmas is there are lots of one-off opportunities to help people less fortunate. There doesn't have to be a big commitment."

So what's on offer? TheSite finds out for you.

Help the homeless

The festive season can be particularly hard and lonely for homeless people. Crisis run Christmas Centres in London and Newcastle from 23-30 December to provide rough sleepers with food, entertainment, housing advice, and even haircuts, dentistry and manicures. The charity needs over 8000 volunteers to make this happen. You can sign up as a 'general volunteer', or if you have a special skill, like hairdressing or dentistry, put yourself forward as a 'services and activities' volunteer. You can apply online and book the shifts you want to do. Christmas day is the most popular, so book early if you're keen to nab that slot.

If you don't live in London, try contacting your local Salvation Army or other homeless shelters to see if they could use your assistance. Homeless charities struggle to fill their night shift slots, so if you really want to feel like a Christmas angel you could sacrifice a night's sleep.

Christmas carolling

Carolling. Is there any better way to feel festive than belting out 'Gloooooo-ooooo-ooooo-oooo-oooo-RIA Hosanna in excelsis'? Thought not. And enjoyable as it is, carolling is also a brilliant way to raise cash for charity. If you fancy vocalising your desperate need for figgy pudding, ring round local charities and ask if you can carol on their behalf. They'll usually provide you with an official collecting tin and then you can bang round the neighbourhood and sing for money. Tone deaf? Local churches will most likely be hosting charity carol concerts and will need volunteers to help sell tickets, seat people, and sell refreshments. Ring around and ask if you can help. Alternatively, check volunteering site Do-it.org.uk to see if churches have advertised any opportunities.

Santa fun runs

On your marks, get set, ho ho ho.

Fancy raising money for charity whilst simultaneously burning off those eight candy canes you just scoffed? Check your local newspaper or Running Diary to see if there's a Santa fun run in your area. For a small entry fee (usually around £10-20) you get given a Father Christmas suit to do a sponsored run in. Lengths of these runs vary from one mile (do-able) to 10 kilometres (might need a few reindeer to drag you along). If cardiovascular activity doesn't mix well with your mince-pie food baby, organisers will always need volunteers to help run the event.

Small things you can do

If you're thinking: "That's all very well, but you know what? I really can't be bothered. I LIKE binge-eating and watching the Queen's speech. Can't I just do something TINY to make me feel good so I can go back to demolishing this tin of Quality Street?" Look no further...

• Pack a gift-wrapped shoebox full of nice things and send it off to a disadvantaged child.
• Shake a charity bucket by a supermarket till.
• Buy charity Christmas cards instead of commercial ones.
• Write a pick-me-up letter to someone wrongly imprisoned through Amnesty International.
• Dress up as an elf and help out at a local school or church's Santa's grotto.
• Invite an international student to come to your house for Christmas dinner.

Volunteering is for life, not just for Christmas

Yes, it's bloody brilliant that you're helping your fellow man this Christmas. Lots of people don't bother, so you're already winning the boast-about-how-worthy-you-are-on-Facebook competition. But why just Christmas? Some people need help all year round. Once the gifts are opened, the dregs of turkey are made into sandwiches, and sales hit the shops charities don't cease to exist. If it felt good, why not consider volunteering more often?

"One of the nice things about our Christmas project is we find a lot of our volunteers are really touched by how they can help others," says Jennie Smith. "We send out a booklet of opportunities after Christmas and find many continue supporting homeless centres."

 As well as the gooey feeling, volunteering looks fabbity fab on your CV. Check Do-it for local opportunities and let the year-round inner-smugness commence.

Updated: 22/12/2011

Holly Thompson