I got to thinking about this after reading the thread in Mechanics, where the necessary spoke was some unusual design and couldn't be sourced. I purchased the appropriate extra spokes when I bought my wheelset so I have that covered ... except I'm not really sure where those spokes are right now.

There is an old touring trick of poking spokes through a cork and stashing them in the seat post. At least that way you'd always know where they are, and in theory even replace a NDS or front spoke on the road if it came up. Do any of you commuters actually store some of your spokes this way?