They remind us when it's time for worship. They offer best wishes for an ailing congregation member.
And sometimes they slip in a funny or sly message that's hard to get out of your mind. Like at the Edgemoor Baptist Church in Claxton, Tennessee.
Someone spotted it this week and alerted Channel 6's sister station WBIR about it.
Noting our ongoing heat wave, someone at the church decided it was just too warm to bother.
So they posted:
"TOO HOT TO KEEP
CHANGING THE SIGN
SIN BAD GOD GOOD
HEAR MORE SUNDAY AT 10 AM"
"This is the perfect sign for summer... we all got a big kick out of it," said Edgemoor Baptist member Sharon Yoder, "Some people maybe have the wrong perception about people who go to church. That they’re all stuffy and no fun. This shows them we do know how to have a good time. And laugh!"
Edgemoor Baptist Pastor Rick Miller said the sign has been up for 40 years and served as the "original social media."
"It’s probably the most visible part of our church," Miller said.
Miller's son put up the sign and said it wasn't an original idea.
You may have seen a memorable local sign yourself.
For example, Washington Heights Baptist Church in North Knoxville often offers an amusing word. Here's one from last year.
We'd love to see photos of signs from around East Tennessee if you'd like to share them. (Let's keep it local, though.)
Feel free to post them to our Facebook page.