Put yourself in your client's shoes for a moment. How would you feel handing over payment for your home inspection only to be handed back one of these items by a smiling inspector?
The Idiot's Pocket Guide to Home Inspections
Yes, you have a great sense of humor. Yes, you're a generous home inspector who cares about his clients. No, your clients will not appreciate those fine qualities when their greatest concern is whether their home is in good condition and you hand them a roll of duct tape, which plants the vague and uncomfortable notion that maybe they should start looking for plumbing leaks that you haven't reported.
Each of these items has some sort of negative connotation, and the effect is that they can raise doubts and faint alarms--and a couple are downright insulting. So, think carefully before you invest in freebies for your clients. Not all of them are good ideas.*