LOL! I so needed this thread when my DD was 3. She literally had me in tears several times. There was a commercial where the friends on a show were trying to help someone get un-stuck, and when they all fell backwards a stuffed animal of one of the characters flew off of the screen. "Nooooo!!!! He fell down! He fell down and I can't see him! Nooooo!!!" Or she would literally cry over spilled milk. "I spilled milk! I spilled milk and it's a mess! I spilled milk and I need more! I made a mess and now I have no milk! Ahhhh!!!" Plus there were times when she was super sneaky, and got to things that I don't even know how she got to.. glitter paint on top of a bookshelf, a sharpie that I swear was in a locked room. Oooh. Fun times.
At 4 1/2 not all of the behaviors are totally gone yet, but it is SO much easier to handle. All through age 3 I did several things that would occasionally work, but with little to no consistency. But, it seemed like the day after her 4th birthday all of the techniques just *clicked* and just about all of them work now unless she is super super tired. I'll share in case they could help you guys out now, or in the future.
Side to Side - I shamelessly stole this one from the show Ni Hao Kai Lan. I'd have her sway side to side repeating "Side to side, side to side" until she calmed down. Usually I'd use this in conjunction with the next one.
BREATHE! - I'd tell her to take a deep breath, in and out and in and out until she could calmly talk about whatever was upsetting her.
Say "It's OK!" - In my brightest cheeriest voice I would tell her to say "It's OK!" over and over again until she did it with a smile on her face. Then I would explain why it was OK. (ie. We'll be able to do that tomorrow/we can get another one/you can try again/etc.)
High Five! - This one is more of a distraction than a soother. I'd tell her to give me a high five. When she did I'd move my hand out of the way. She'd laugh and laugh, and then we'd "try again." Finally when she was laughing too hard to remember whatever little incident had her spun up, I'd let her high five my hand. She'd get all excited that she did it and run off to go play with something else.
Sing me a song - "Please please! I love the way you sing!" Another distraction, but a little bit of a longer one and usually used in the car when I couldn't directly look at her and confront the issue.
Visualization - "Can you lean your head back and close your eyes? I want you to think about something." Then you invent something fantastical that calms their mind and makes them happy. For DD this started out as "imagine you are playing with the butterflies. You're spinning around in a field full of flowers as all the butterflies are fluttering by." Occasionally we've had to implement other elements to keep her interest, so now it's "Imagine you're riding on a beautiful unicorn through a field of flowers when you see a rainbow. You and your unicorn ride up the rainbow to a beautiful castle in the clouds surrounded by butterflies." This one is AWESOME at bedtime when she won't settle down, and also works well in the car on long trips.
Now, like I said, at 3 a lot of times these would backfire. I would do some of these things and she would say something like "I'm too upset! I can't right now!" or like with the "High Five!", she'd get SUPER mad that I wouldn't let her high five me the first couple of times. Or with "It's OK!" she'd say "But it's NOT ok!" So, I'd have to backtrack and start something else. But, now at 4 and 1/2 most of these work just about all of the time. And, honestly I usually can start out with just plain attempting to reason with her about the situation before I even resort to one of these techniques.