VirtuaWin - VirtuaWin is a virtual desktop manager for the Windows operating system (Win9x/ME/NT/Win2K/XP/Win2003/Vista/Win7/Win10). A virtual desktop manager lets you organize applications over several virtual desktops (also called 'workspaces').
IceWM - icewm home page . Bug Tracking. If you have a patch, a bug report or a feature request to submit, please do so at the icewm project page at SourceForge.
Sysinternals Desktops - Desktops allows you to organize your applications on up to four virtual desktops.
i3 - A dynamic tiling window manager designed for X11, inspired by wmii, and written in C.
9Desks - up to nine virtual desktops
Fluxbox - Fluxbox is a window manager for X that was based on the Blackbox 0.61.1 code.