"If your computer is less than three years old, and you use it mainly to surf the Web and write e-mail, chances are you don't need a new one," says Peter Rojas, founder of the tech sites Engadget.com
. Likewise, no need to trade up your DVR ("They all do essentially the same thing") or your iPod, if you use it primarily to listen to music ("An iPod Touch or Nano may have less space than your current model"). Your high-def TV is fine, too—at least for now. "Lots of new HDTV display technologies will be coming out in the next couple of years," Rojas says, "so you should wait to upgrade."