One of simplest ways to curb your contribution to climate change, while saving on energy bills at the same time, is to replace ordinary incandescent lightbulbs with compact fluorescent blubs (CFLs).  A CFL consumes about a quarter of the energy used by an incandescent bulb; while you might have to pay more for CFLs than ordinary bulbs up-front, the electricity saved over the bulb's lifetime will more than make up for this.  Another advantage to CFLs is that they can be recycled.  They do contain a trace amount of mercury, so be sure and recycle them at a toxic waste disposal site (unsurprisingly, fossil fuel interests, led by ExxonMobil, have hugely exaggerated the mercury content of CFLs - the truth is that they contain a very tiny amount, and the environmental benefits far outweigh this disadvantage). 

Over its lifetime, an average CFL will keep about 700 pounds of carbon dioxide out of the atmosphere.  If every household in the US replaced all its incandescent bulbs with CFLs, approximately 90 power plants could be retired.  Talk about fighting global warming!  Finally, unlike older fluorescent bulbs, new CFLs produce a light indistinguishable from that of incandescent bulbs; they can also fit into any socket made for incandescents.

Find out more about energy efficient lighting!