Tab Scissors for Chrome
More About Tab Scissors
If you have at least two tabs in the selected Chrome window, it will split that window into two smaller side-by-side windows. All the tabs on the left side of the selected tab will stay in the left window, and the rest will move to the window on the right.
It is especially helpful for those who have lots of tabs opened at a time.
This extension works great with Tab Glue (http://bit.ly/WjGnm7), which will glue all those pesky Chrome windows back together.
Version 1.2 Update: You can now also perform a glue or cut using a shortcut specified on the chrome extensions page. Default is Alt+S to cut, Alt+G to glue, Alt+A to glue all (including minimized windows)