Alton Brown has stated in the past that there is no place for unitaskers — tools that do only one thing — in a kitchen. Yet he has a kettle, a device for boiling water with no other purpose, and an espresso machine, a device for making espresso and steamed milk with no other purpose. And then there's knives.
I have to disagree. There is a place, in the kitchen just as in the workshop, for single-purpose tools that do one specific job well, and for multitaskers that can be used for a range of purposes. What there is NOT a place for is poorly thought out or poorly constructed tools that are intended to perform multiple tasks, but which don't actually do any of them well, or single-purpose as-seen-on-TV gadgets that do one exceedingly uncommon job that you could, with only a little more effort, do just as well with other tools that you already have.