Sometimes a birthday calls for sincerity. This card is for the other times. Bold, bright, and to the malodorous point — it’s a reminder that aging is mandatory, but acting your age never is. Say “Happy Birthday, You Old Fart” without sugarcoating it. Hand-printed, hand-folded, hand-stuffed-inside-that-little-plastic-sleeve (which happens to be commercially compostable). Get it while the gettin’s good.