I've only been able to test it on my computer, so it may not work correctly for everyone.
Instructions: -Set Skyrims resolution to the same resolution as your monitor.
-Click the box in the Skyrim options for windowed mode.
-If you want to launch your game via Steam, start the game through Steam and alt-tab out before you click the "Start Skyrim" button.
-Start Embiggen Skyrim.exe and click "Start Skyrim"
-It will attempt to launch TESV.exe if Skyrim is not already running, or will maximize the window if Skyrim is running.
Here's the link to it on the Nexus: http://www.skyrimnexus.com/downloads/file.php?id=218
Please report any problems.