Well, San Francisco has been buzzin’ with new parking meters that can be paid wireless via your cellphone or even re-charged via a website.
Here’s a bunch of neat stuff on how to hack parking meters.
*NOTE: This is informational only, not for real life, don’t blame us if you get arrested. :p
If you can find a similar-sized coin from another country, that might be a good way. I used to use Korean won coin