The word “philanthropy” may conjure up images of wealthy donors who build entire hospital wings and endow foundations, but you don’t have to be a Rockefeller to make an impact. Nowadays, the lean economy is forcing more and more charities to meet a higher demand with a lower supply, so the adage “every little bit helps” has never rung truer. Here are ways to spread goodwill this season, one small act of giving at a time.

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Donate empties.Instead of contributing to a landfill, give used ink and toner cartridges a purpose. Hundreds of nonprofits collect and resell empty cartridges to companies that refill, recycle, or remanufacture them. Nonprofits with recycling programs include Habitat for Humanity (habitat.org), Meals on Wheels (mowaa.org), and the Humane Society (humanesociety.org). Each cartridge can fetch up to $5 for the charity of your choice.

Surf for the Earth. Powered by Google, Ecosearch.org returns the same search results but with an environmental kick: The site donates 100 percent of search revenues—created by displaying ads alongside your query results—to nonprofits, such as Rainforest Alliance and Sierra Club. Go to ecosearch.org, or make it your computer’s default search engine.

Less than $10

Plant trees. For $5, The Nature Conservancy plants five trees in Brazil’s Atlantic Forest (plantabillion.org) to help reverse global warming. Having protected 117 million-plus acres around the world, The Nature Conservancy is designated a “Top-Rated Charity” by the American Institute of Philanthropy.

Feed the hungry. The Food for All initiative (foodforall.org) has partnered with 8,000 grocery stores nationwide to help end world hunger. Each time you check out at participating stores, tack on a small donation ($1 and up) to your bill; more than 84 percent of your donation dollar benefits local antihunger nonprofits. The contributions add up fast: A Miami-based grocery chain recently raised $747,000 in just six weeks.

Provide pure water. An estimated 1.1 billion people don’t have access to clean drinking water. The Children’s Safe Drinking Water organization (csdw.org) distributes packets with a powder that makes unsanitary water drinkable; $7.50 provides one child with a year’s worth. Also check out howtocleanstuff.net, a website of clever cleaning tips submitted by readers; for each tip it publishes, the site donates 25 cents to the Clean Water Fund (cleanwaterfund.org).]

Less than $25

Adopt a polar bear. World Wildlife Fund (worldwildlife.org) offers symbolic adoptions of more than 50 species—from a tiny clownfish or blue-footed booby to a majestic polar bear or elephant—and 82 cents of every dollar goes directly toward conservation.

Dump the junk. Junk mail is a terrible waste of 80 billion trees per year. For $20 annually, Tonic Mailstopper (tonicmailstopper.com) gets you off junk mailing lists—and plants five trees in your honor.

Moisturize for good. When you spend $20 on Lush’s Charity Pot body cream, made with natural oils and fair-trade cocoa butter, 100 percent of proceeds (minus taxes) goes to support animal, humanitarian, and environmental foundations, such as Oceana and Bicycles for Humanity (usa.lush.com).