Well, the Windows Vista sidebar was done away with for some good reason. It wasn’t too popular and some considered it a resource hog and a waste of desktop real-estate. But there was always a set of people who loved it and wanted to see it back on their Windows 7 desktop.
Some were even not happy when they upgraded to Windows 7 since all the gadgets were getting hidden behind the open windows.
For all such folks, there is 7 Sidebar.
7 Sidebar emulates the sidebar of Vista in Windows 7 and also adds some extra features to it. There is no need to install it. Simply run it as a gadget.
The 7 sidebar can hold gadgets and stays visible even if a window is maximized. With one click you can switch to a window-manager with live-thumbnails. The thumbnails can be configured to update even if the window is minimized.
Download: 7 Sidebar.
If you loved the Vista sidebar, you definitely want to try this one out!
Check this if you Windows Sidebar does not start.