Recs.
Updated
Tiling window manager, extensible in LUA, supporting Tiling/Tabbing/Static window layout configurations.
Specs
Pros
Pro Rich facilities for organising windows
In MS Windows, you can have your windows piled on the virtual desktop, hidden away, and then this repeated in N workspaces. The workspaces have the same backround image, and moving windows between them is a pain.
In Notion on the other hand, you can have several windows in each tile, accessible through tabs. Then, obviously, you have the tiles. New desktops are easily added, and easily accessed. They can be named, and host tiled or non-tiled windows.
In addition to these hierarchies, there is also a pop-up frame, shared by all desktops, where you can put windows you need now and then, no matter what desktop you are visiting at the moment.
In short, it is simple to keep a large number of windows organised in Notion.
Pro Designed for keyboard control, but also very easy to use with a mouse.
Not having to lift the hands from the keyboard more than absolutely necessary, is a very important aspect for all of us who are good at touch typing. Notion was designed by someone who was sick and tired of productivity repercussions associated with the hunt-and-peck paradigm of the normal GUIs.
That said, he also made sure that it is easy to use the mouse, would you choose to do so. For instance, when you want to move the boundary between two tiles, you do not have to hit a two pixel wide strip right at the boundary, a wide lane is there for this, so that you do not have to shift your mental focus to the hunting-and-pecking.