Well for me personally...
Mine are when my thoughts start coming one on top of the other. One will start and before I can finish with one thought the next is coming and I will struggle to go back and finish the other thought and the next one is coming on and i am trying to back up and go to the other one and it gets overwhelming yet I am trying to keep up with all of them because some of them are very interesting! (or so I think) LOL
I get ticked because I want to slow them down or track them but have no way of doing it.
If I am talking to someone or typing on the board when this going on it is pure h**l- I have to back track and stop and check to make sure I completed what I said or wrote.
I have a hard time listening or keeping track of what people are saying because my brain is going so fast and going ahead of their conversation. I am planning what I am going to say and can't stop myself and often will keep interrupting which I hate!
What is a drag is if i am arguing with husband, I can't keep up with the conversation because my mind is racing ahead, so i can't keep up with what was said! LOL
So if he backtracks and quotes me on something I become so flabbergasted!!!
If I am sitting around alone... the thoughts will just free flow, sometimes I will talk to myself to let it out.
That is a few examples off of the top of my racing mind!