Do any window managers allow me to snap windows to the sides of the display? Can you recommend a Window Manager for the Mac? I would like to have a keyboard shortcut that would snap a windows to the left or right half of my screen.
SizeUp is exactly what you need:


  SizeUp allows you to quickly position a window to fill exactly half the screen (splitscreen), a quarter of the screen (quadrant), full screen, or centered via the menu bar or configurable system-wide shortcuts (hotkeys). Similar to "tiled windows" functionality available on other operating systems.