Since its launch last year, Giving Tuesday has catapulted from a grassroots movement to a global force for social good.
The unified effort to kick off the holiday giving season takes place on the Tuesday following Black Friday and Cyber Monday. This year, Mashable is teaming up with Google+ to host the first-ever "Hangout-a-thon," featuring 12 hours of programming from a range of novel and exciting causes. We've rounded up 15 other worthy campaigns that you should know about beyond the Hangout-a-thon.
See also: Happening Now: Hang Out and Give Back
Share an #UNselfie. Giving Tuesday harnessed the power of the selfie — love it or hate it — and spun it on its head. Share an "unselfie" instead, a photo of yourself showing support for a cause you care about. If you can't fit yourself and your cause into the frame, try taking a photo holding a piece of paper and writing out the name of your cause. Make sure to tag #GivingTuesday, too.
Just Detention International's Words of Hope campaign. In an effort to bring hope to some of the world's most marginalized, Just Detention International is asking people to write letters to survivors of prison rape. A similar campaign last year helped bring holiday cheer to some 10,000 prisoners.
GlobalGiving's Gift Cards for Good. You can buy a holiday GlobalGiving gift card for the holiays in amounts ranging from $10 to $10,000 and let the recipient choose where to give. One special project donates to a Typhoon Haiyan relief fund.
Right to Play's 20 for 20 for 20 Campaign. Non-profit Right to Play is hoping to raise $100,000 in an Indiegogo campaign, aiming to bring 20 Olympic athletes together to improve the lives of 20,000 children in the developing world through sports programming.
The Case Foundation gives $100,000. Beginning on Giving Tuesday, the Case Foundation will highlight one creative way to give back on its Facebook page each week. It will also give away $100,000 in matching grants to non-profits that sign up their campaigns on Crowdrise.
See also: 15 Holiday Gifts That Give Back
GoCoin donates bitcoins. Bitcoin processing company GoCoin will donate the Bitcoin equivalent of $1 to the Boys and Girls Club of Santa Monica every time someone tweets with the hashtag #Go4Good.
Glee fans can meet the cast.. Glee is giving Gleeks everywhere a chance to meet the entire cast when you make a $5 donation to Invisible Children through an Omaze campaign.
tinyGive donates $12,000 on Twitter. Micro-donation platform tinyGive is partnering with several non-profits to give away $12,000 in a Giving Tuesday social-matching campaign on Twitter. For the first 2,500 unique donations of $5 or more that are mentioned on Twitter, tinyGive will add $2 to the gift.
CafePress sells personalized ornaments for the Red Cross. Decorate your Christmas tree with an ornament that gives back when you purchase a personalized holiday ornament from CafePress, which donates proceeds from the sale to the American Red Cross.
Melinda Gates matches Catapult donations. Melinda Gates is matching all donations to this Catapult campaign for Typhoon Haiyan relief for mothers and children.
See also: 10 Empowering Apps for Social Good
Diapers.com donates vaccines. Giving Tuesday is the day to make a big purchase online for diapers for your little one. Diapers.com is partnering with the United Nations Foundation's Shot@Life campaign and will donate one life-saving vaccine with each $50 purchase.
Casa's charitable cooking boutique. Casa has created a holiday shopping boutique with OXO products and will donate 10% of the proceeds to Cookies for Kids' Cancer.
Microsoft matches donations to YouthSpark. Microsoft is matching donations to YouthSpark up to $250,000. Microsoft Store shoppers also get a $25 gift card to "spend" with different YouthSpark causes.
CVS Caremark gives $25,000 to non-profits: CVS is giving away $1,000 grants to 25 causes nominated by its employees.
Charilty Miles' #TurkeyTrot: Timex Sports is sponsoring Charity Miles' #GivingTuesdayTurkeyTrot. If you're not familiar with the charity fitness app, its sponsors donate money to charity for each mile you walk, run or bike.
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