Save Energy -- Switch to Compact Fluorescent Bulbs (CFLs)
As opposed to incandescent bulbs, CFL's last up to 10 times longer, use about 75-percent less energy, and will save you around $30 over its lifetime.
On the downside, they contain poisonous mercury and therefore need to be recycled instead of thrown in the garbage, which can be a hassle. If they break, it's trouble, but you can visit Energystar.gov for cleanup instructions.
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