What would be the legal ramifications if I make my last alimony payment in pennies?
Unless you could prove that the only practicable way you could pay your last alimony payment (which I would imagine would number at least in the hundreds if not the thousands of dollars) in pennies, then if your ex-spouse objected to your attempt to pay your last alimony payment in pennies, the court would likely conclude that your attempt to pay alimony in pennies was primarily for the purpose of inconveniencing and unduly burdening your ex-spouse, would likely require you to pay in cash (in large bills) or check (one check, not a separate check for every dollar you owe), and sanction (fine) you for misconduct.
Paying fines and obligations in pennies was legitimately funny (even if mean-spirited) the first time it was tried. Now it’s just banal, petty, burdensome, silly, and offensive. Forewarned is forearmed. Proceed at your own risk.