I would be interested in knowing if there is still a limit on how many cents a business must accept for payment.
There never was a legal limit to that in the US as far as I know. Someone with more legal knowledge can correct me if I'm wrong, but as far as I know there is neither a legal minimum nor a legal maximum of change or bills that any private party must accept as payment for an incurred debt. Government agencies don't get the same leeway though... they can refuse cash altogether, but once they say they will accept cash as payment they have to accept any legal tender combination of bills and coins provided. Again, as far as I know (I know I say that a lot lol, but it is a disclaimer that although I'm 95% sure that I'm right, I'm not a legal expert and could very well be wrong on this matter, so take it for what it's worth.).
Here in Canada, they can refuse to take more than a certain number of each type of coin. I forget the specifics, but I think it's the equivalent of a roll (or thereabouts), but I do believe that Troodon is correct, that in the US there is no such law. (Or at least that's how I remember it. On another note, has anyone tried to transport that many pennies? I had to carry $50 worth once and that was pretty heavy. I can only image what it must have taken to move that many pennies! (And I wonder how many wheats, and possibly IHs there might have been in the bunch!)