I was the recipient of hundreds of leftover film canisters from a local photo organization and wanted to make a relatively easy, low-cost project that I could do with students. This version requires no soldering, but hopefully someone will take this idea to the next step and add arduino capability. These little lanterns are safer and last longer than candles. Shades are interchangeable to match theme or mood.
One bright or ultra bright white LED
One coin cell battery, 3V
Transparent film canister with cap
Toilet paper tube
Needle nose pliers
Glue or double sided tape
Step 1: Homemade battery holder
Cut 2 cardboard tabs, 1/2"x1" each. I used a toilet paper tube, since this is needed in a later step. On one end of each tab, cut off corners and bend.
Use a glue gun to glue tabs, bent side out, into canister cap.