Do you know the sleeping half pigeon pose? I *love* that one...
I do now! I'll add it to the set.
My favorite is the one where you lie on your back (obviously, because lying down stretches are the best) with your ankle to your knee and pull back on the knee leg. It's my go-to, though obviously I need to do it more / more often since apparently my hips are a disaster.
The other one I like is an extension of that one. Holding the same position with your legs and removing your hands, return your bent "knee leg" foot to the floor and push your "ankle foot" down to the floor beside you. Try to keep your upper body as flat on the ground as you can.
It looks like the lying on the back one is sometimes called reclined pigeon or, much better IMO, dead pigeon pose.
The one I like takes the dead pigeon a little further - lie on your back, cross your legs at the knees. Then lift your whole leg-pretzel towards you , so that you've hinged at the waist by 90 degrees, and grab the outsides of your feet. I don't know if I'm explaining that very well. But it's a good hip stretch.
I've heard that one called the pretzel stretch, and it's useful when the other hip stretches don't q u i t e get to the part you need stretched.