Cube taps come in all different shapes and colours but on set they are always needed. We'll have an area for batteries to be charging, laptop tops and hard drives plugged in, then there's lighting and monitors. These always us to share the love (the power), just know how much power each item you're plugging in needs, don't want to break the breaker or blow a fuse.
White and black foamcore can be picked up at a Dollar store or Walmart. The white foamcore can be used to bounce the sun or a lighting onto a subject or object. The black can cut or flag the sun or light.
Screwdrivers are always needed on set; tightening of a tripod plate, or making adjustments to equipment. I recently purchased this set of screwdriver keychains. Fun fact, if you need to tighten your tripod plate, keep a quarter in your camera bag and use it to tighten your tripod plate!
Zip-ties, rope, & double sided tape are all items that could come in handy on your next production.I recently used a piece of rope to act as a secondary method to secure a suction cup on the hood of my car. If the suction gave out, the rope would stop the whole rig from hitting the road at 60KM. Double sided tape or the 3M tape that doesn't mark the walls is a great way to "hang" something on the wall, hide a microphone or light. Just test the area before applying it... oh the stories I could share!
I can think of at least 5 people I would "borrow" this last item from on set and never return them. Now in my defence I would buy packs of these around the holidays and include them with gifts as thank yous... but the #1 item I used on set was sharpies. Sharpies are a camera assistants worst nightmare but as a director and producer I would use them on my shotlist, callsheet and just to make notes. For a tool I used all the time, I never had one on me! Big thank you to those that gave me theirs!