Quite a while ago, I was involved in baiting an attacker in a somewhat different way, but with the same goal (destroying the value we were providing to them). After the attacker figured out what was going on, they issued a somewhat credible threat to damage the company's machines (they included some details demonstrating they had access to a couple internal machines at some point), attacked and DOSed them, and persistently tried spearphishing them for months afterwards.

I guess I'd just say, (a) doing this sort of thing responsibly sucks a lot of the fun out of it, and (b) don't underestimate the risks of things going pear-shaped. You could be buying yourself a lot of ongoing grief. Something as everyday as that spearphishing attack can be nerve wracking - even after making annoying the crap out of everyone by repeating how to be careful with email, there's no way to be sure it won't hit, and the next thing you know people are sitting around with upper management having conversations nobody wants to have about network segmentation and damage mitigation.