One of the most loved and hated feautures of visual studio must be the form designer.

Creating a simple form/user control layout usually is a breeze. Setting properties and adding events is easy.

Setting up the toolbox to use you own controls can be a bit harder and getting the ToolBoxIcons to show up can be a pain. Using third party components by visual inheritance can throw of the designer. And using multiple inheritance on designerables can be really hard.

So what are your favorite 'hidden' and or obvious visual studio designer features.