Irradiated Software - Cinch
http://www.irradiatedsoftware.com/cinch
"Cinch gives you simple, mouse-driven window management by defining the left, right, and top edges of your screen as 'hot zones'. Drag a window until the mouse cursor enters one of these zones then drop the window to have it cinch into place. Cinching to the left or right edges of the screen will resize the window to fill exactly half the screen, allowing you to easily compare two windows side-by-side (splitscreen). Cinching to the top edge of the screen will resize the window to fill the entire screen (fullscreen). Dragging a window away from its cinched position will restore the window to its original size. "
Use Fluid to bring mobile web apps to your Mac desktop
http://arstechnica.com/journals/apple.ars/2008/05/16/use-fluid-to-bring-mobile-web-apps-to-your-mac-desktop
"After I discovered Fluid's ability to change browser agents, however, I realized that it has quite a bit of potential to create SSBs for mobile web apps that are a bit more friendly to desktop real estate."
PD Tweaker
http://www.multisolar.com/software/PDTweaker
"PD Tweaker is an Application Enhancer (APE) plugin that addresses a few shortcomings in the initial release of Parallels Desktop (build 1848) for Intel-based Macintoshes."
The SphereXP
http://www.hamar.sk/sphere
"The SphereXP is a 3D desktop replacement for Microsoft Windows XP. "