The Lifehack weblog has a great roundup of clever uses for household spray lubricant WD-40. The most surprising? WD-40: Cures arthritis. My father-in-law swears by this. He is a retired Air Force mechanic and when his knuckles and knees get grouchy he squirts them with WD-40. He says it works every time. Apparently WD-40 can also remove lime buildup from your faucets, prevent light bulb socket corrosion, and remove sticker adhesive or tree sap from your car. What do you use WD-40 for? Let us know in the comments or to tips at lifehacker.com. — Gina Trapani WD-40 Top 10 Tips [Lifehack]