I store my students mini offices in pencil boxes in which we call our "Writer's Toolbox". In addition to our writing mini office, we store our writing pencil (any pencil that has a design on it- They love these and take well care of these "special" writing pencils), eraser, Mr. Spaceman (spacing stick from Really Good Stuff), post it notes, and mini dry erase marker and eraser.
Check these mini writing offices out at my Teacher's Notebook or TPT store.
P.S. The first 5 people to blog about the mini writing offices on their blog with a link back to my blog will receive one free copy of a mini office of their choice. Be sure to email email@example.com after doing so and please leave a comment. :)