This seems to come up often here and the correct answer inevitably gravitates towards "don't do it". I would agree. I just wouldn't feel comfortable sending alo

This seems to come up often here and the correct answer inevitably gravitates towards "don't do it". I would agree. I just wouldn't feel comfortable sending along software/application with a kill switch in it. Could you imagine what you could be accused of if someone were to find it? Also, you'd be opening up yourself to a huge liability if the project were of any type of size or capable of generating any type of income. Let's say you are on a big job with reputable people and a sane payment schedule or you're doing a website for someone's lawn mowing service in which you can hold on to the code, either way, there's no conceivable reason to add a kill switch. Now, if you insist on serving that type of clientele, and providing them a product without payment, then have fun with that. Spending any more time than necessary devising schemes on how you're going to get lowlifes to pay you is just the time of time suck that's going to keep you settling for that type of client.