Power tools are well and good, but often its the random bits and pieces which save the day. In this week's Top Tools, it's all about the attachments that make good tools better. A three-in-one hole saw sticks onto your drill; a flexy-straw extender makes caulking a breeze; and a portable monster welder . . . Well, that's just cool. Our friends at toolmonger.com give us the low down here.