Fold/Infold control

Hi,

I'd like know if anyone has a handy information on a Win Forms control which, once docked on the left/right side can fold/unfold in the same way the Visual Studio tab views (Properties, Solutions view etc) act when mouse is over. If there's no immediate implementation hint I'd appreciate to learn where I could find it for purchase. The controls are of "post-it type" (juste text displayed) and "toolbar type" (that is with buttons on it). Many thanks!