cstrike

Using this script you can strafe using the keyboard instead of the mouse! Easy off and on button - all controls are default until you turn it on, and go back to default when you turn it off! You have to bind +gostrafe and +nostrafe to different keys in order for this to work (e.g. bind mouse4 +gostrafe and bind mouse5 +nostrafe). When you press the +gostrafe key you can strafe, and then press the +nostrafe key to stop strafing.
Yawspeed is what affects the keyboard turning speed - a higher yawspeed means a higher turning speed (all this is done without using the mouse). Change it if you feel the need.

Spoiler:

alias +stra "+left; +moveleft"
alias -stra "-left; -moveleft"
alias +straf "+right; +moveright"
alias -straf "-right; -moveright"
alias +gostrafe "-left; -right; -moveleft; -moveright; -forward; unbind a; unbind d; bind a +stra; bind d +straf"
alias -gostrafe "bind a +stra; bind d +straf"
alias +nostrafe "-left; -right; -moveleft; -moveright; -forward; unbind a; unbind d; bind a +moveleft; bind d +moveright"
alias -nostrafe "bind a +moveleft; bind d +moveright"
cl_yawspeed 450