Rumor has it that if you you wrap your celery in tin foil before placing it in the fridge it will last for weeks, and be fresh and crisp when you need it.  They say it also works for nearly 7 weeks for stored broccoli and heads of lettuce.Have you tried this method? I learned that recently with friends.Another great use of foil

When bread (or other food) that's baking is getting dark on top, but isn't fully cooked on the inside yet, make a loose tent from foil and place on top of the item.