Living with my partner means we are two crazy artists in a two-room apartment (hence why we are crazy half the time) and we use the space to max. Currently we are at war over paintbrushes and my partners familiar (a 26-toed feline fiend from gods knows where) gets into everything.
Highvoltage and highfrequency electrics being somewhat dangerous and me not wanting to have to fight my partners occult legions with my half-finnished arsenal of deathrays I had to put things safe, this also keeps the chalkmarks, black candles and ectoplasma out. So all the really bad stuff is in a case.
Update: My Little Mad Scientist kit now lives in the basement .. in my Little Workshop of Horror!