Stick 'Em Up is a desktop sticky notes application, similar to Apple's Stickies application which is included in Mac OS X.  Stick 'Em Up lets you create notes in different colours and sizes that can contain rich text and graphics.  

With Stick 'Em Up you group your notes in to categories, only the notes in a selected category are shown on screen.  
 
You can navigate through your categories via the application menu, keyboard commands, or with a small categories list window.