Legal "Weapons"

I think I need to start carrying something that could be used as a weapon with me. Nothing illegal (which is why I don't carry my machete around), but a few things work in a pinch. I don't think my keys and driver's license are going to cut it against a sudden zombie threat. Here is a short list of possilbe legal weapons:

1. A Swiss Army knife (I know, I know, I should have been carrying one of these all along)
2. A flashlight (A magnum brand flashlight, complete with batteries, becomes a very effective bludgeon, and oh yeah, good as a light source too)
3. A roll of quarters and a sock (actually, I do carry this around. good for a impromptu bludgeon, and the local arcade)
4. A dog choke chain, wallet chain, or heavy necklace (all can double as brass knuckles-though they may not speak to your fashion sense)
5. Strong language (always good in a pinch)

Any Suggestions?