Originally Posted by Kimmo

If you have any old computers around you can pinch the backup battery off the motherboard.

Originally Posted by NJgreyhead

I need CR 2032 batteries occasionally, for bike computers and lights. My drugstore wants US$7.50 each, and WalMart wants $6.40. However, WM also sells bike taillights for ~ $6.99 that contain 2 of the CR 2032 batteries. The taillights are basic, steady and flash mode only, but are decent and have the rubber loop "bracket" that attaches easily to a seatpost, etc. Not bad.