My grandma used to say if she bought your wart, for a dime, it would go away.
I feel like there were others.... But I remember my mom perpetuating the Santa lie after someone at school told me the truth. When my folks went thru a divorce a few months later, my trust was broken, and I couldn't trust my mom. It was a very hard time for me! I vowed back then I was never going to lie to my kids.
My kids are all adults and my oldest will tell you the three times I've lied to her: once when she ordered 'a lobster and fries, please" at an expensive seafood place, I pointed to the kids fish and chips on the menu and then told my dd that they cooked the lobster differently here, once when we were surprising them with a trip to DisneyWorld, I lied about the dog sitter picking up our dog for a playdate and when she was really little I told my Christmas birthday preschooler that everyone put up lights for her birthday. :P
We never did Santa. They have all told me as teens and young adults that they like knowing I will always tell them the truth about anything they want to know.