Since old Konfabulator got to be Yahoo! Widgets, I simply dislike the application. :\ And I used to use Konfab A HELL LOT.
Today I'd use Avedesk... it's widgets are fully configurable, and it must use less system resources than Yahoo Widgets.
Windows Sidebar doesn't worth. It's pretty, but simply doesn't worth. Uses a lot of memory and it's installation is kinda complex.
Samurize is even more complex. Though it has nice widgets like system info and the fact that YOU can write your scripts, it seems to make the system slower after some long time active.
So if you're not satisfied with Konfa... errm, Yahoo, go for Avedesk.
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