Maybe it's the writer in me, but I always seem to have way too many old, useless pens lying around. Here's something I might do with them... Office Depot is honoring Earth Day with a writing instruments recycling offer this year. Bring in 10 pens, pencils, markers or other writing instruments (any brand) and receive a coupon for 50 percent off a new product from Newell Rubbermaid (maker of Sharpie, EXPO, Papermate, etc.) Your old writing instruments will be recycled through a really cool eco-friendly company called Terra Cycle. You can turn in your used writing instruments when you check out, or see any in-store associate. The offer is good through April 23 (Saturday).