If your pen is under warranty, get it fixed or replaced. That's a no-brainer. If it's out of warranty, do the math. A basic pen might cost $20-$50. A repair could cost $15-$30 in parts and shipping. But you also have to factor in the time and hassle. If the repair is more than half the cost of a new pen, just buy a new one. And if you've had the pen for more than six months, you've likely gotten your money's worth.

Sometimes the issue is just the cartridge connection, which you can clean or adjust. But if the battery's dead or the coil is fried, it's not worth it. Upgrade to a new model—you'll likely get better performance and features anyway.