I love this thing

I've added Firefly by Titanas to the inventory, and there's a tip below to help you get the most out of it.

Back in the 1990s I owned an effect that used a squeeze light (shaped like a BIC lighter) that was attached to an elastic pull that was sold as a magic dealer effect to light up a flashbulb inside a glass saltshaker. I can't remember the inventor, but I used it all the time. I lit up everything I could fit between my hands: beer bottles, soda bottles, glasses, quartz crystals, anything... It was easy to get into and ended with both hands completely empty. Audiences loved it! I loved it!

Eventually the gimmick's battery died, and the squeeze lights were no longer able to be acquired.
For about the last 4 or 5 years I have tinkered with different method to create this trick and improve on it. FIREFLY is better than any version I came up with.

Here's the tip:
The instructions don't include a practical setup of the pull that you can use to palm the device with one hand. A pull is described, but it would require both hands to get it into position correctly. The pull that is described allows for a very flat openness of the hand concealing the FIREFLY, and there's even a fancy move to show both sides of the hand. This makes for excellent video demonstrations of the trick, but none of this is really necessary for real world use.

How to fix this:
I took an ordinary washer and attached it to a piece of elastic cord. The washer is a large 1 1/2-inch diameter washer. These are available at hardware stores. I attached the elastic cord to the hole in the washer. I attached the FIREFLY to the washer with two pieces of monofilament fishing line and clear double-sided tape. I pinned the elastic cord to my jacket, behind and just under my right arm so that the washer is hanging at the bottom edge of my jacket, just under the fabric. At any time, I can reach back to the edge of my jacket with my right hand and palm the washer so the FIREFLY can be brought to the front to produce the effect. This way I can use it when I want, anytime, with no reset. (and no rubber bands!)

• Cut four notches into the washer to hold the fishing line in place.
• Use the grooves in the FIREFLY to hold it against the washer with two loops of fishing line.
• I only use the device this way, so I added double sided clear tape to the back of the FIREFLY.
• The hole in the washer can be used to attach your elastic to the washer - you don't have to drill it.
• You want it to have some weight, so the washer hangs down to the edge of your jacket. Use two washers (soldered, glued or taped together) if one feels too light.
• Paint the washer black first. It's not really necessary, but it reduces the chance of a glint of light catching the shiny washer as it retracts. 

It's just like palming a coin, but it's on a pull.