If Bitcoin does not fail or somehow is made illegal in the US, which does not have to matter in the long run.
A Bitcoin can be worth easily 2012 $5000 in 20 years. Thats just the Facebook value if applied to Bitcoin.
And Facebook became worth that much in 10 years.
If Bitcoins stays legal in most part of the earth which it should.
They sky is the limit.
In 35 years, if both the dollar or and the Euro and the chinese currency have crashed they can easily be $200 000 each.
You need to take into account that there are lots of "positive" effects built into the system.
Almost everyone who buys Bitcoins wants to make a profit and the majority will thus not sell at a loss.
This could easily create an strong upward spiral. That will pull in more and more investors and people as they witness this happens.
Some will even protect their value by placing bidwalls.
All it takes is for 100 000 people to own 210 Bitcoins each and they will have them all.
Still for the economy to work, they need to be spread among many more.
And for this you have the network effect. Which on the internet can go quick.
If there are 100 000 who use Bitcoin today, each gets only 4 persons to understand and invest in Bitcoin.
There is a 4 times increase in the amount of people.
Value goes to 40.
Next year everyone gets 4 new, and this year Bitcoin reach a million users.
Value goes to 160
Next year 4 million. Now the news might start to pick it up seriously.
Value goes to 656
Next year 16 million.
Value 2624
Next year 64 million.
Value $10,496
Thats in 5 years
Not impossible that this will happen over 35 years if Bitcoin is still here.
There is certainly enough money for this to happen. Since it wont have to be spent on 21 million coins.
But Bitcoin could be at only $1500 in 35 years.