I don't do it as much anymore. I used to when in my early 20's all of the time. There was a couch that I really liked. The one I have now is starting to fall apart.
I cannot do that - I have too much back damage from being rear ended multiple times (including once where I was trying to turn left and was hit by someone going 40MPH). I can only sleep on a bed (and barely at that). I would enjoy being able to nap on the couch though.
I do on occasion, and did often when my kids were younger since the living room is right next to their bedroom.
We bought a Sactional by the company LoveSac (makes giant beanbag chairs) and it is the most comfortable, configurable couch ever. I currently have it laid out as a queen sized bed so it's comfy for sleeping.
I slept on a couch for a while after my ex and I split. It was one of those reclining bucket-seat styled couches. I’ve been in accidents and have plenty of damage to my shoulder and back, and everyone in this thread is smart for avoiding sleeping on them because of their back issues. It is not fun.