A widget is a small useful single purpose tool. Outside of a computer, a magnifying glass, a pair of nail clippers, or one of those citrus peeler thingies
would be called widgets.
Yahoo Widgets, Konfabulator, Vista Gadgets are collections
of widgets that rely on a common 'widget engine'. But a widget doesn't have to be part of a collection to be a widget, nor does it have to rely on a widget engine...it just has to do one thing....and be small.
A better synonym for a widget would be 'tiny tool'.
By all rights, most of Skrommel's tools
are widgets and I would call many of the coding snacks
I wouldn't call FARR a widget because it is too complex and really does a lot more than one thing, but I would call mouser's DYDLO a widget.
So based on this definition, I think it would be safe to say that we all
use widgets and it's just a matter of listing your favorite tiny tools to answer this question, or more specifically, the tiny tools that are always visible on your desktop, or at least visible when they are doing their job. Most tray tools (but not all) wouldn't be desktop
widgets because they do their job from the tray and not on the desktop.
And for me, my 2 favorites would have to be my own DClock2
, and wordzilla's Pop-Up Cody
. They are the only desktop widgets that are always running that I would be more than quite annoyed if I had to close either of them for any reason.