Oceanbreeze had some good points there.
For me, I have a variety of things. I just mainly work to get my mind on something else. Current living situation makes some things harder than others. (We are living with my MIL, but hopefully next summer our house will be completed.) Depending on the severity of the attack, I will choose from:
Knitting, crocheting, sewing, puzzles, coloring with crayons, art with colored pencils, acrylic paints or watercolors, Exercising with therabands and resistance bands, playing the keyboard (I use no power to it. Since I can't hear, I just run my fingers on the keys and no one in the house is bothered by it.) If it's a real bad situation and I am able to, I will go for a drive. I am fortunate enough to live near the beach. I go down to Ocean Ave on Palm Beach and start at the North side and run down to the South side and breathe in the salt air. Parking is too expensive, so I drive just under the speed limit and enjoy the view. If I am feeling strong enough, I will take my rollator and go for a walk around the neighborhood. If it occurs at night time and everyone is at home and I can't get away due to weather or health, then I go to a quiet space I have made in the closet. I sit in there with no lights and just do deep breathing. If all else fails, then I contact my therapist by the house phone and then we get together on Skype.
I hope to get back into some of the exercises I did when taking gymnastics many moons ago.