As many people have predicted, the dollar continues to be a bad investment.
You could compare the value of a dollar against many things but gold is a rather standard currency too:
http://www.kitco.com/
Gold is now at $541/oz.
Over the last year, gold has risen ~27% versus the dollar. Over the last 5 years, it's increased about 104%.
Is gold worth a lot more than it was a year ago? Not really. Is the dollar worth a lot less than it was a year ago? Yep.
There are probably other tangible assets that would make a decent investment, but I'd recommend people not hang on to too many dollars. It still seems likely to sink quite a bit more. Housing prices have been stabilizing, but that's under conditions of a dropping dollar value, so even the housing market is beginning to come back down (as seems inevitable).
I don't normally recommend buying things that rise, but I do recommend selling IOUs/dollars, while they're still worth something. There's not as much of a downside to tangible assets compared to the dollar. There's probably something better than gold to invest in if you keep your eyes open, but don't invest in anything that's a target for assest seizures or taxes, just to be safe.
Anyway, have fun, and invest safely.