Dead battery. Now what?
It can happen: You leave the key on while going in to a restaurant for a bite to eat. Now your battery is dead. Push starting is next to impossible on your own, and even with a couple helpers it can be a real chore. For about $90, you can have this 1 LB little marvel jump start your bike, and power up your laptop and smartphone. It only loses about 10% charge per year, so you can throw it in your panniers and forget about it until you need it. Pretty cool eh?