How can I grind coffee without a coffee grinder?
In my opinion, the best option is to have someone grind them for you. Ask your friends--someone may have a grinder you can borrow, or would be happy to grind them for you in exchange for some cookies or part of the bag of coffee.

If you have a local coffee shop, talk to the barista (over the latte' you just bought) and ask if he/she will grind your beans for you. I've heard even the mighty Starbucks will grind your beans for you if you ask nicely enough.

If you want to do it yourself, you need to find a way to get the beans down to grinds. Some ideas:

Mortar and pestle. Be careful not to make Turkish coffee powder instead of the more chunky grinds you want.



Rolling pin. Put the beans in a heavy Ziploc bag or similar, and have a go at them. Roll, whack, smash.



Have a nice, heavy frying pan? Ziploc bag again, hammer away.



And speaking of hammers...



No, not that Hammer.  This hammer.