Its obvious I was talking about an electric one. However, abacuses technically produce heat while being used (from friction) and my electric calculator does too. So maybe you should have specified if you meant an electric calculator... ;)

Obviously, I should've specified that, though it takes a lot of effort to produce noticeable one...

But the claim was that what it does CURRENTLY IS its purpose. You are just saying that eventually, people will learn to take advantage of the side effects (which may or may not actually happen IMO).

Well, as I said, the intention is up in the air, so as long as the creator would neither deny or confirm it, via updates, we might consider it as its secondary purpose, if it STILL produces those side-effects CLEARLY, according to the creator...

But for the sake of simplicity, I'll just give up the argument for now.