Here are some suggestions/ideas:
Change.org is an online platform for petitions. Add your voice to many issues that arise, often alerts via email, or you can sign up via the site.
Votesmart.org is a wonderful site that enables visitors to look up laws that are in the law-making process, and to find out who votes on what. This empowers you to write to your representative (you can email via the site) to make your voice heard.
Politifact.com offers fact-checking on many issues.
TheHungerSite.com offers more than just feed the hungry. Includes veterans, literacy, environment, and more.
Goodsearch.com offers a search site powered by Yahoo to help fund charities whenever you do a search online.
Greatsunflower.org is an interesting project to help study the bee population. You get free sunflower seeds and then you keep track of the number of bees that visit your garden.
-Read up on the issues and learn about activist activities. Earthhopenetwork.net offers some neat articles.
-Recycle. We’re fortunate in our area to have curb side recycling, and the guy who led this told me it seriously impacted the landfill to add another 20+ years to it. You can recycle by giving to the recycling center, giving old stuff to shelters such as women’s shelters, animal shelters, or even churches (who help folks who lost everything).
-Volunteer. Check with local churches or shelters to help out. Work in a soup kitchen, clean out kennels in a dog shelters, or help build houses for Habitat for Humanity.
Do you already do anything to give back the world? Post in comments, or share ideas, links, etc. I’d love to hear your thoughts on this.