Black and Decker LED snakelight for $10 today at Home Depot.
Uses 2 x C batteries.  A set of batteries comes with the light, although
they are not alkalines, best to have extra batteries on hand.

this is the model;
http://www.tylertool.com/blackanddecker69.html

I've found these useful in Vanagon/Westies for camping activities and/or
after dark troubleshooting/repairs.
The snake base allows you to prop it up and aim the light where you need it.

The snake section is removable, turning it into a more standard flashlight
size form factor.

Good deal for $10
Get one for each of your vans!