I've come up with a solution for trying to find something in your black BMW side cases, or any motorcycle saddlebag for that matter, in low light conditions. Usually when I'm digging for something in my bags in a low light situation I'm either holding a light in my teeth or holding my phone with the flash illuminated in one hand. This has frustrated me far too long and I've taken action.
First LED lights have come a long way. They are now bright, cheap, and really light. These two pen lights were purchased at ACE hardware for less than $5 each.
Next I bought Sugru at Radio Shack for about $12. What is Sugru? Sugru is the world's first mouldable glue that turns into rubber. You can learn many ways to use it at sugru.com or instructables.com. You can order it online or buy it at Radio Shack, Micheals, or Lowe's. You mold it into a shape you want, and then let it cure for 24 hours.
Last LEGO's. I could've just attached the lights to the inside of the bags. But that would make them not useable for other situations in which I need light. Like, dare I say it, but a breakdown on the side of the road, or maybe just setting up camp a little too late in the day.
I let everything cure for 24 hours before setting everything together. And here is the final product with the LED light snapped in place and on. You can see how much this light helps see what is inside the case. The 2x8 LEGO sticks keep it in place while the bike is in motion, but allows me to remove the light when needed to illuminate other things. I used 2 packs of the 3 pack of Sugru. One piece of advice is to buy more Sugru packs than you think you need. There really isn't a lot in one pack, and you find other things in your life you'll want to fix or hack with this stuff once you start using it. The last pack of the 3 pack, I used to replace a broken zipper pull on a messenger bag that I use all the time. Lastly, if I want to remove any of this you just use an Exacto knife to separate carefully, and then the remaining residue you can rub off with your fingers.