WinArranger Free 

WinArranger helps you to use your workspace more effectively by arranging windows on your computer screen in the most optimal way. It can even hide borders and captions and system taskbar. Multi-monitor configurations are fully supported. Freeware.
arrange windows tile windows multi-monitor screen organizer desktop organizer

HeldUp 

HeldUp keeps any application window in full view on the desktop. HeldUp is resource friendly because it's so small (70kb), and it's simple and easy to use. Just grab the icon from the system tray, drag and drop it on the window to hold up.
topmost ontop top float hwnd_topmost utilities system tray window systray

AppAway 

AppAway is the easiest way to hide any program. The program will not appear on the screen, in the taskbar or when you alt+tab. Just drag the AppAway icon from the system tray onto the software you want to hide. And AppAway is SMALL, it's only 72kb
hidden privacy private utilities system tray window systray