Although I'm a fan of Vista's SideBar, there's not *that* many gadgets that I regard as unable to live without.
However, Donavon West has just released what must be the most useful gadget for users of Windows Home Server.
His ShareMaster gadget (now compatible with x64 versions of Vista without the WHS Connector S/W installed as well) is a dream.
The gadget simply shows 6 icons that represent the main shares exposed by WHS like so: -
Clicking the icon obviously opens an explorer window at that location, but the real beauty is simply the ability to drag a file/folder onto the icon to copy it to that WHS location.
This saves a huge amount of time (open windows, mouse clicks etc) when managing the content between your workstations and the WHS.
It has become a standard gadget now on all of my vista machines.
Check out the gadget at
http://www.homeserverhacks.com/2008/04/sharemaster-for-home-server-gadget.html