Originally Posted by Midian
Add cigarettes and drugs (mostly pain killers and muscle relaxers) as currency items for trade with stupid people.
This is exactly why when I turn 21 I will stock up a bit on various types of long shelf-life booze. I don't even drink, or plan to, but there are people out there who will want some spirits for entertainment, medical, or other reasons. I think clear liquors in plastic (more shatter-resistant) bottles are probably the best candidates, but I'm no expert.
After reading an article on SHTF in Argentina, I noticed the author stressed having a few "luxury" items (even hotel bottles of shampoo/moisturizer, bags of instant coffee, unopened spice bottles, etc.). This could be a really prudent, zero-cost precaution if you know where to get them.