that I don't think I've seen mentioned.

For storing flat sheets of duct tape and electrical tape grab some free bumper stickers if you ever see any, either throw away or stick the stickers on your bumper, save the backing material and put your tape on that.

It makes a nice reusable packet of tape that will lie flat if you don't want to roll it around something.

I made up a couple sheets of both and have them stored in my PSP's.

JohnE

My favorite way to store duct tape (I use the Gorilla brand) is to wrap about 10 feet of it around my Nalgene water bottle just above my metal cup that nests with the bottle. It weighs almost nothing and is always there as long as I have my bottle.

Wax paper (found in many kitchens) should also provide a decent easy release backer for tape.

"...Peel-n-stick backing off of mailing labels.."

That's what I use..

I wrap it around a pencil kept with my kit. Protects the pencil as well.

Here is another one.
I use those fake credit cards that companies send periodically in the mail as a foundation. They just happen to be the same width as the tape. I wrap ~6ft around it and then have a nice compact package that lays flat in my kits.

Brome

Waxed paper doesn't work, for me. The tape tears the paper up, sticks in places, etc. I have used cooking parchment paper (silicone coated), which held up better. I don't know about long term, though. 1-2 months is my longest test-time.

i've found it difficult to use from a card or paper; so i wrap it round the mini maglite on my keyring and it's always with me. By the way what are those torches they use in the CSI franchise?
They seem to be standard, like glocks are as firearms. Except what is that David Caruso uses?
The Sock

I like those small rolls of duct tape from gear aid - take a gander at http://www.rei.com/product/627518. 100 inches, and small enough to stick in my pocket. A little pricey at $1.50 a roll, but I don't feel the pain if I just grab a 2-pack on my way to the register now and again. I once had the flat type duct tape in my sack, but could never find it when I needed it. Flexible nalgene water bottles kinda don't hold the duct tape the same.

During a first aid session I quizzed the Scouts on how to tie up a bandage. They all completely overlooked the miles of duct tape that covered their nalgene bottles (and had been there for many hikes) instead resorting to a bit of FAK tape and paracord.

I think what David Caruso is using what we call in the biz, a special effect...
I have trouble seeing anything else when he's in a scene, what with him chewing all the scenery to bits...Sorry, can't stand his acting or his characterizations.

I love seeing what I call the X Files flashlights in the various cop shows. It's amazing what a little bit of artificial smoke can do to a beam of light.

JohnE