While not really tactical gear it is equipment. Every emergency kit should have some form of alternative light source and generally it has been a flashlight. The LuminAID Solar Light is one of these items. These make for nice bugout kit items. And for $19.95 ( $17.95 if you order 3+ or $15.95 if you order 10+ ) Pictures linked from their website.

The LuminAID Solar Light is a solar-powered, inflatable light that packs flat and inflates to create a lightweight, waterproof lantern. Safe, Sustainable and ultra-portable, the LuminAID provides up to 15 hours of LED light and can be easily recharged in the sun, ideal for recreational use outdoors or in the home as an extra light source. Tuck it away in your first-aid kit or hook it on your backpack for your next adventure or trip!

•Push Button Switch with HIGH and LOW settings
•8-10 Hours LED light on HIGH setting
•14-16 Hours LED light on LOW setting
•Recharges in 6-7 hours of direct sunlight
•High-efficiency monocrystalline solar panel
•Lithium-Polymer Ion battery with hundreds of recharge cycles
•Weight: 3 oz
•Dimensions: 8.25″ W x 12″ L (when not inflated) Waterproof up to 1 meter deep and can float (IPX-7)
•All components including battery are lead-free and RoHs compliant