For what I need to drag around, I have one of those roll up toiletry bags that can hang up or be rolled to go to class or move to another machine. Here is a link to something like I have:
http://www.amazon.com/Household-Esse...g+toiletry+bag
I like it because I have compartments of different sizes -- I can carry thread, scissors, bobbins, rotary cutters, etc.