I was watching a Survival 101 video and it has really made me appreciate one of the most useful items ever invented by mankind - plastic
trash bags, particularly the large 20+ gallon heavy-duty ones. They can be used for anything: a raincoat / tent, mattress / blanket / pillow, shoes /
waders / other clothing (warm when stuffed), water storage / purification / laundry, emergency condom / masturbation aid, weapon (just put a rock in it), fishing / trapping tool, disposal of unwanted corpses, washable underwear / toilet paper replacement, airtight storage container, crude air filter mask, etc, etc, etc - the list is endless.
So why not use it as an advertising medium as well? Most stores that give away them cheap plastic shopping bags put their logo and stuff on it, so why not sell custom-made trash-bags promoting FSP, FTL, or whatever else we'd want to promote? One can always keep an extra trash bag in one's pocket or something, in case you need it for survival purposes (i.e. it starts raining), for some emergency picketing, roadside trash pickup volunteerism, or just to throw it over a police officer's head just before you start running. It would also get great visibility in the neighborhood, especially if there are no strict rules about not putting your trash out on the curb early - like a week in advance.

One possible downside is that some people might see the association with trash as a negative, an anti-advertisement so to speak. But hey, you can over-analyze anything. No one gets any mixed messages about a Ron Paul sticker attached to a STOP sign... Or do they?

Also, I know the common answer with Free Staters is "you do it", but, hey, just throwing an idea out there has some value too.