guys, i'm not saying a total collapse or "replacement" of the dollar is impossible....but, if this happens i believe you'd see it on a global scale with every currency....not just the US...as currency is'nt tied to anything in almost any country...it's an "idea"...
i think more likely in the next few years you are looking at a continued "change" in what the dollar will buy...inflation...which would be good for your gold.....like joe says, look at history...
the history of what $1 would buy you:
100 years ago- 20 loaves of fresh baked bread....or 1 days wages
75 years ago- a first class steak dinner
50 years ago- a day at the movies with popcorn,candy,drink...
25 years ago- 2 tacos
today- a standard pack of chewing gum, a small candy bar, or 4 shares of kry
25 years from now- i'm guessing we will have done away with "loose change" by then as it will be cheaper to wipe your butt with dollar bills than to buy toilet paper....