Agree with dhickey about guns - although I'm not sure if he is actually just being facetious.
But yes guns are actually a very good commodity to invest the dollar in. Gold is another. The value of gold stays very consistent, and only decreases with big gold discoveries (such as the California Gold Rush). Basic economics = scarcity of resources determines value. You can't just print more gold...
I was not kidding at all. I made 40% on an AR-15 that I held for a few months. I made 20% on a Ruger Mini-14. I just got an LR-308 that took a few months to get. I paid $1k total for it. They are going for $1.5k + on auction. I have actually decided that I want to build and SR-25 clone, so I may sell this one. I would keep it and add parts but, for some reason, I ordered one with no forward assist and no dust cover. If I do get 1.5k for it, I might just order an M1 Scout Squad and piece together the SR-25 over time.
If you are buying guns or ammo as an investment, just don't buy on auction. Put in orders with retailers and wait. I did the same with ammo, other than some mill surplus I bought already in enblock clips for my Garand.
Ammo is still going up as well. Even if people weren't freaking out, guns and ammo tend not to lose value. Just buy the common stuff you can get in bulk; .308, .30-06, .223, 7.62x39, 9mm, .40, .45, etc. Stocking up on the international stuff like 7.62x39, 5.28, even 7.62x54 (still cheap) may be a good idea. There has been talk of shutting down importation of ammo. These will become almost non-existant if that happens. All sorts of fun stuff to shoot a little bit of this stuff up with as well.
It doesn't show it, but a few years before the chart started the price spiked way up and quickly plummeted. It doesn't take dollar inflation into account but you can still see that gold is anything but a stable asset. Its also not an income generating asset (like stocks or real estate) and you could even argue that its negative due to the costs of storing it.
I do think it has the potential to be a good investment for the next few years, though. Historically gold prices have increased steadily during times of extreme pessimism and doubt (ie: NOW!). Obama's talk about "green shoots" and "cautious optimism" is keeping the price down to some extent, but if America truly is going down the toilet economically, you'll see the price shoot up.
A lot of corporations are betting on this. I'm sure you've noticed a huge increase in "send us your unwanted gold" commercials. Its an ideal situation for these types of businesses because people are desperate and willing to part with gold just to keep their heads above water. They're anticipating a big payoff. This is further evidenced by all the gold ETFs that have been popping up.
Anyway, I'm not as pessimistic as some...I don't think this will be the "end of capitalism" or the death of the DOW, but we're definitely in for some rough times ahead. I'm investing a good amount of money in companies that are a.) in a country not severely affected by the downturn, b.) in a position to "weather the storm" or even thrive or c.) paying huge dividends.