Small screwdriver, long tweezers, and needle nose pliers have saved many a day sewing away from home. I also take a power strip with long cord. I keep the round one that rolls up a 25 ft cord in my car trunk. I keep a small power strip in my sewing machine rolling cart. I keep duplicates of all my sewing supplies in a case in my car. I never have to pack to go to a workshop or sewday other then fabric and pattern.
But I got to sewdays/groups/guilds/workshops/classes at least once a week. I'm going to one today as soon as the other Nana gets here to take charge of the greatest grandson in the world! I take care of him during the day so he won't have to go to daycare. He's so stinking cute.