AutoHotKey script to assign capslock to ctrl. It is optional to remap capslock to either left ctrl or right ctrl.

caps2ctrl.ahk

;
; AutoHotkey Version: 1.x
; Language:       English
; Platform:       Win9x/NT
; Author:         William Isaac Miller <wimiller@cs.umb.edu>
;
; Script Function:
;    Remaps the CapsLock key to Control, and moves CapsLock to Right Control.
;

;;; Default script settings

#NoEnv  ; Recommended for performance and compatibility with future AutoHotkey releases.
SendMode Input  ; Recommended for new scripts due to its superior speed and reliability.
SetWorkingDir %A_ScriptDir%  ; Ensures a consistent starting directory.


;;; Remap CapsLock to Control.
CapsLock::Control

;;; Move CapsLock to either Right Control or Left Control.
; LControl::CapsLock
; RControl::CapsLock