Snap feature for Mac? Coming from Windows I have gotten extremely used to the Windows Snap feature, which resizes a window when it's dragged to the screen edges.

However, it's not built into OS X. Are there any 3rd party utilities that add this functionality?
For window arranging:


SizeUp  $13
Divvy  $14
Breeze  $8
ShiftIt  Free
Mercury Mover  $20
Optimal Layout  $14
Cinch  $7 
Moom  $10