Following on from the Rowdy Toddlers thread, I'm looking for words of wisdom about dealing with the less cheerful variety of toddler.
DS1 is 2.5 and is great fun when in a good mood, but regularly has foul moods which drive me mad. Today he woke up that way (after sleeping 8pm-8am, so I don't think it's a sleep issue) but the switch can be flicked at any time, it seems.
He starts off by asking for something - already in a whiney, near-crying voice. It's loud, high-pitched and drives me to distraction. If he doesn't get his own way, he is undistractable and repeats his demand over and over, until he works himself up to a complete meltdown.
A good example from today: after doing some fairly full on Playmobil playing with him on the floor this afternoon, my gammy hip was playing up so I sat on the sofa. Cue "Mummy go on floor!" (MGOF) to which I explained variously that I was sore (noooo, MGOF), we could do Playmobil on the sofa (nooo, MGOF), started Playmobil enactment on sofa (very loud whining, MGOF), did he want to read a story/cuddle/have a drink (MGOF), tried the How To Talk So Kids Will Listen thing (ooh, you look really upset, you really wanted Mummy to play on the floor - blank look and then MGOF, wail).
By this stage he's sobbing MGOF and so I told him that he was being too loud, the noise hurts my ears and that if he didn't stop and play nicely, he'd have to go in The Corner. No difference, so The Corner it is. 2 minutes of screaming and sobbing later, I ask if he is ready to come out and play nicely. Of course, he wants MGOF. And so we go on.
We get into this stalemate situation a few times a day and it's miserable not being able to move him on to the fun stuff.
I feel like I'm using The Corner for stuff which isn't that big a deal - he isn't biting, or endangering himself etc - but it just grinds me down.
DH was last night wondereing if we should send him for extra nursery sessions - he thrives there a few mornings a week - but I feel that is almost an acknowledgment that he prefers the nursery to me 
and I want to have fun with him while he's little and while I'm on maternity leave.
Aaaargh, help!