Harley's Tour-Pak Luggage and Saddlebag Interior Light Kit p/n 54331-04 works well and is easy to install. It is a little pricey at $120.00, but it does work well.
+1 for flashlight. I heard years ago that America spent hundreds of thousands of $ to develop an ink pen that would write in zero gravity of space. The Russians just used a pencil.
I use LED "Puck" lights. Cost about $1 each. Need 3M outdoor double sided tape to mount, otherwise hot weather makes them fall off.
+1 for the puck with LEDs. I have one in my TourPak and 1 in each saddlebag. And I also agree with you to use industrial strength tape. I used to find them in the bottom of my bags when it was hot.
They work great and they're bright enough. Bought them at Walmart for a few bucks. I think it's a pack of 2 or 3 but I'm not sure how many.
Found an LED light at WalMart from GE. It has on it, can be removed from the housing and pivots side to side, has a clip on the back or can be glued or screwed to mount the base. Works on 3 aaa's. Cant find it on the net right now, but I'll post pics next time I take some.