I prefer to think of 'hack' and its variants as neutral terms that can, in context be either good ('Look what I hacked together!') or bad ('They hacked into the servers').
(Actually, the way usually explain it to non-techies: duct tape. Everyone understands what duct tape is meant for: it won't necessarily win any awards for style[1], but it's powerful, and it sure as heck gets the job done in a pinch, and quickly too! I find that analogy generally holds well enough, whether we're talking about black-hat hacking or 'real' hacking.)
(Actually, the way usually explain it to non-techies: duct tape. Everyone understands what duct tape is meant for: it won't necessarily win any awards for style[1], but it's powerful, and it sure as heck gets the job done in a pinch, and quickly too! I find that analogy generally holds well enough, whether we're talking about black-hat hacking or 'real' hacking.)
[1] Most of the time, that is: http://www.google.com/search?hl=en&q=duct%20tape%20cloth...