Why not just get her a bag of these, they can be scattered around, if one breaks, no great loss (and no guilt):

http://www.countycomm.com/light10.htm

I got the blue ones as they were out of white at the time, and they work great, gave a couple to my son at college, stuffed a couple in my PSK (Doug's kit, they slid right in) and gave a few away.