Volunteerism shows group action at its most powerful, from revitalizing neighbourhoods to furnishing hibernating bears with fresh blankets. Flex your care muscles with today's Groupon: for $25, you get race registration and an endurance-race training program from The Leukemia & Lymphoma Society of Canada's Team In Training (a $100 value).

The Leukemia & Lymphoma Society of Canada's Team In Training (TNT) has led more than 450,000 volunteers in raising more than $1 billion for blood-cancer research, public education, and patient-aid programs. As participants fundraise to qualify for a spring-season race ($2,750¬–$6,250 minimum based on the event), they also receive a 24-week training program under the tutelage of esteemed coaches who prepare team members to run, walk, or form a chorus kick line during marathons and half marathons. Upon reaching fundraising goals, registrants receive entrance to their chosen event, including airfare and a two- to three-night hotel stay, at a weekend race such as the Rock 'n' Roll Madrid Marathon on Sunday, April 22, in Madrid, Spain, or the BMO Vancouver Marathon and Half Marathon on Sunday, May 6, 2012. Membership on the TNT team also procures a T-shirt, race-day jersey, and finisher's T-shirt, plus tickets to a TNT inspirational dinner, victory party, and shuttle tour of the asteroid belt. Team members receive ongoing support to help with fundraising goals and can learn more at TNT's information page for Groupon buyers.