Help with Late Thank You Cards

I responded with a private note to this, but no one else responded aso I'm sending this in LATE. lol Here is a simple late thank you:
[b]Thank you for [i] ( insert gift)[/i] last [i](insert time: month, year, Spring, Winter, week)[/i]. Please excuse the delay of this note. Even though it has taken some time to write, your kindness (or generosity) could not go without a written thank you. Know that your kindness and friendship is truly appreciated. Thanks again.[/b]
If, as in my own humiliating situation, your new husband promised to drop them off to the Post office and you found them moths later in the trunk of his car you won't want to open them up just to add a line of apology. SO consider adding a funny line right on the back of the envelope like, [i]“We fired the mail fairy when we found a bag of cards hidden in the bedroom closet,”[/i] or maybe, [i]“If you noticed this card was late, you win! Congratulations! Report to HQ for your secret assignment.”[/i] You get the idea … something that will make the recipients chuckle, but also let them know you realize you made a faux pas..