Things you have no time to do once you have children.
Wash your hair
Before I had children, I washed my hair every day. Now I wash it when I'm going to work, which is usually twice a week. The other days I use half a can of dry shampoo and a hair bobble. And now, because it's getting colder, I can add a hat to my repertoire of things-to-stop-people-noticing-that-I-never-wash-my-hair. Hurray for Autumn!
Get engrossed in a good book
First of all, finding the time to get engrossed in anything when you have children happens about as often as a blue moon. And even when the stars do align, it's never actually that simple. For example, as soon as I sit down with a book and start getting into it, one of two things happens: Either the napping baby wakes up, woebegone by the tragedy of being completely unable to find the bunny snuggle he so desperately needs to sleep (despite the fact that said bunny is actually tied to the strap of his sleeping bag and two millimetres away from his face) OR I wake up an hour later with a stiff neck and my book on the floor, by which time the baby needs to be woken from his nap.
As a mother - and I'm sure the same is true for many fathers too - you don't so much sleep as fall unconscious. But it's the kind of unconscious that becomes instant, wide-awake alertness at the smallest sound from your offspring. And once the wide-awake alertness has happened, the unconsciousness is suddenly hard to find. Also, you probably have at least one child trying to get into your bed by this point, which renders sleep completely impossible anyway.
Let's be honest here, when you're sleep deprived and lying horizontally in a bed, you're almost never going to pick sex over sleep. And if you do pick sex, your other half probably knows it's mostly just to get him to shut up and go away, or it's a guilty pity shag because you feel a bit sorry for him. Lovely.
Give a shit about your house
I used to clean my house religiously. I would just about come out in hives if it wasn't clean. Now I manage to hoover, mop and keep the bathrooms clean. Most weeks you could write in the dust - but please don't - and I hardly ever get around to putting my own laundry away. Don't even get me started on the endless fucking washing.
Take a long, indulgent bubble bath
I used to love soaking in the bath. I've probably spent weeks of my life just lying in hot, soapy water if you add it all up. Never happens now. Now I plan to have a long, indulgent bath... And then I spend five minutes hastily scrubbing myself down before dragging myself up the stairs and into bed. Because otherwise my husband would probably come home at 11:30pm and find that I had fallen asleep and drowned.
I'm not talking food shopping, because we have overcome the issue of dragging bored children to the supermarket by having our groceries delivered. I'm talking about when you need some new shoes or jeans and you have something specific in mind (or can only shop within certain ranges because you're an unorthodox size), and you won't be satisfied until you find that specific thing. I once tried to take Toddler Taylor with me when I went shopping for a new coat. He was bored after 10 minutes and it was only by sheer good fortune that I stumbled across exactly what I was looking for fairly quickly. Otherwise? Not advisable. Stick to online shopping.
I'm sure you can all think of many more examples - and please leave them in the comments/tweet me if you can -, but these are the ones that spring immediately to mind for me. The thing is, I actually have no fucking idea what I used to do with my time before I had children, although I know exactly what I would do with it now!