At the moment I've got an entire Matriska Doll of RPG stuff.
I've got a plastic string envelope that has some pocket-mods for "Wyred", cards I made for "Final Stand", business card sized character sheets for "Warrior, Rouge, and Mage" writing utensils (cheap mechanical pencils, eraser, pen), and some D6s.
Next I have a messenger bag to hold two or three binders with additional game print-outs (thank you college library for a chance to print many of the free games I've acquired!) lined paper, spiral notebooks (lined paper as well, but I hate tearing out pages.) and yet more dice. Sometimes my "Heroes of the Multiverse" card game goes in as well.
Finally, there is a large black gym-bag with more dice, two shoe-boxes full of cardboard terrain and Mecha miniatures, (I've fallen in love with "Armor Grid Mech Attack" from DTRPG) as well as binders and folders with character and control sheets and of course, yet more dice.
Electronic devices don't really factor into my collection - I'm over protective of them and don't want anything getting damaged in my bags. Most of my books are at home, though print-out filled binders take their place.