We both call each other Boo. As in, “Hey Boo, can you get me a drink?” “Sure Boo, here you go.” And we sign emails “Love, Boo” sometimes.
It probably sounds like we’re rapping or something, because I hear “my boo” a lot in urban music these days. 
But I swear, we started saying it before we heard it anywhere else.
Sometimes, I call him Love or Lovey. He doesn’t have a good nicknamey name, but I do, so he uses my shortened first name a lot.
“Spousal unit”
Honey, sweetie, baby, gorgeous…occasionally we use real, actual first names. Sometimes “mommy” and “daddy” when the little one is around.
Paulie Bear and Linnie The Pooh when we want to make friends vomit.
Me to her: Hunny Bunny, m’luv. and the Spanish Inquisition.
Her to me: Usually, honey or Hunny Bunny.
We generally only use first names when we’re angry or about to start a serious conversation.
Peace - DESK
Babycakes.
Which most often devolves to 'cakes.
Or if we’re feeling sexy: spicecakes or hotcakes.
Or if somebody is in a bad mood: crabcakes.
That’s exactly what I was going to say. We’ve been calling each other Boo for more than a decade. Now it’s everywhere. Did we start something?
We have been known to also call each other Nummy Muffin Cuckoo Butter, which may have come from MST3K. I can’t remember anymore. But Boo is our default nickname. I call my kids “Pooh” from Winnie-the-. Of course, they’re little boys, so they probably think it comes from poopy, which is their favorite word.