At the moment I use Ctrl+Super+←/→ to align windows on my screens with compiz.
I don't really like using compiz as I don't like the Alt+Tab feel to switch windows, among other niggles.
Are there any environments that have Ctrl+Super+←/→ or similar to split windows as a default?
Today I switched to Gnome desktop. You can use the exact same shortcut to split the screen.
Of course most window managers (see What is the difference between a desktop environment and a window manager?) offer shortkeys to change window position and size, but with wmctrl you can control such things simply yourself, e.g.
wmctrl -r :ACTIVE: -e 0,200,200,640,480
to change the active window's size to 640x480px and position it at 200, 200. See man wmctrl for the whole story.
Once you figured out the commands you want just assign them to the desired shortcut using your desktop environment's GUI.
You can edit almost all Compiz keyboard shortcuts to your liking in Compiz Config Settings Manager.
My answer is Cinnamon Desktop. I switched from Unity about 2 months ago and couldn't be happier. Super+direction moves windows in many different ways. You can do left/right half, top/bottom, full-screen and even corners with just super and directions. By the way, it's default functionality. Check it out.
