"You don't say"
"No s--t"
My dad always said "Get off your dead ass" when he wanted something done.
A friend I hung around with in my teens often quoted a verse from a Bob Dylan song when he saw a girl he liked: "She's got everything she needs."
Some people still say "That's bad," when they want to say it's really good.
"Knock my socks off."
When a guy's zipper is down, "Hey, you're losing altitude."
I had a black co-worker. We had so much fun at work. I learned many sayings from her & she would ROFLOL when I imitated her.
When she wanted to say a guy was good looking, she'd say "Ain't no shame in my game."
And when she'd jokingly get mad at someone: 'Side yo head." (I'll smack you on the head)
When another woman screwed something up at work, she'd say, "She's a mess in a dress."
When we talked about a celebrity, "She got them chips." (means she's wealthy)
When she wanted to say someone was making something complicated, "Too much drama for your mama with a comma."