SizeUp is a window management tool for OS X. You can use it to move apps to different corners of your screen or different monitors and spaces. SizeUp is best controlled by keyboard shortcuts and makes keeping your desktop workspace organized so easy.

You can check out the full SizeUp Cheatsheet here.

And below are a few of my favorite SizeUp shortcuts:

⌃ ⌥ ⌘ ← Send window left
⌃ ⌥ ⌘ → Send window right
⌃ ⌥ ⌘ ↑ Send window up
⌃ ⌥ ⌘ ↓ Send window down
⌃ ⌥ ⌘ M Make window full screen
⌃ ⌥ ⌘ C Send window center