This should really be solved in software...
However, I remember trying to map capslock to control on windows a few years back. It involved becoming an administrator and entering an opaque hexadecimal key into the registry.
Simply popping off the key is probably easier.
Oh, on linux it boils down to "setxkbmap -option ctrl:nocaps", which doesn't require root...
SharpKeys [1] is the tool I've kept in my toolbelt to do this for several years now. (Though I swap capslock for an extra backspace or escape depending on mood and amount of Vim in my life at the time.)