Ratpoison

/usr/share/xsessions/ratpoison.desktop

[code]
[Desktop Entry]
Name=Ratpoison
Comment=This session logs you into Ratpoison
Exec=/usr/bin/ratpoison
TryExec=/usr/bin/ratpoison
Icon=
Type=Application
X-Ubuntu-Gettext-Domain=ratpoison-session
[/code]

~/.xmodmaprc

[code]
remove Lock = Caps_Lock
remove Control = Control_L
keysym Control_L = Caps_Lock
keysym Caps_Lock = Control_L
add Lock = Caps_Lock
add Control = Control_L
[/code]