PyGrid!

Aquasnap is a powerful window manager that helps you arrange and organize multiple applications on your desktop with minimum effort. It allows you to achieve maximum multitasking, especially if you own a high-resolution monitor or a multi-monitor setup.

BetterTouchTool is a great, feature packed app that allows you to configure many gestures for your Magic Mouse (1 & 2), Macbook Trackpad and Magic Trackpad (1 & 2) and also Mouse Gestures for normal mice. It also allows you to configure actions for keyboard shortcuts, normal mice buttons and the Apple Remote. In addition to this it has an iOS companion App (BTT Remote) which can also be configured to control your Mac the way you want.

WinSplit Revolution is a small utility which allows you to easily organize your open windows by tiling, resizing and positioning them to make the best use of your desktop real estate.

ShiftIt is an application for OSX that allows you to quickly manipulate window position and size using keyboard shortcuts. It intends to become a full featured window organizer for OSX. It is a complete rewrite of the original ShiftIt by Aravindkumar Rajendiran which is not longer under development.

AltDrag allows you to move and resize windows much easier. When you have it running you can simply hold down the Alt key and then use your mouse to drag any window, and it doesn't matter where in the window you click. This is especially useful in netbooks, with respect to the small screen and touchpad. It simply allows you to do more with less mouse movements.

MaxTo is a small Windows program that divides your monitors into regions. When you maximize a window, it will no longer fit the entire screen, but only the region it was maximized into. Your windows are neatly organized into the grid you have defined when they are maximized. MaxTo has been described as a tiling window manager.

GridMove - A window management tool that can quickly arrange your windows into desktop grids.GridMove is a program that aims at making windows management easier. It helps you with this task by defining a visual grid on your desktop, to which you can easily snap windows. This program comes bundled with some predefined grid templates, that can be easily swaped, but also has ways of creating custom grids or sharing grids made by others.

TaskSpace is a simple Windows application intended to group ANY applications in a single window(task space) to provide fast and easy access to multiple applications simultaneously(no Alt+Tab switching and/or searching for a program in the taskbar is required).

HyperDock adds Windows 7 like features and more to Mac OS X.

WindowGrid is a modern window management program that allows the user to quickly and easily layout their windows on a dynamic grid.WindowGrid gives functionality to the normally useless right mouse button when moving a window. Doing this will enable the grid snap mode.

Windownaut is versatile window management app that let's you define keyboard shortcuts and active areas on your screen to resize an position the windows on your desktop.

KWin is a window manager for the X Window System, and is in the process of becoming a Wayland compositor. It is an integral part, and the default window manager of the Plasma Workspaces, but it can also be used on its own or with other desktop environments.

WindowSpace is a powerful desktop enhancement utility for large monitors, widescreens and multi-monitor systems. Once installed, it allows you to manipulate windows in many new amazing ways – snap windows to the screen edges and other windows, move and resize them with keyboard shortcuts, maximize vertically or horizontally, pin on top of the other windows, hide from view, minimize to tray, and it’s just the beginning!