First of all I must tell you that the title you gave to the thread it totally wrong because the thread isn't related to global economy as Euro has nothing to do with the global economy but European economy. And, even if your prediction regarding Euro's value loss is correct then still that won't have any impact on the global economy.

I know that there are some chances that Euro may lose a lot of its value in future, but still I think you have predicted this thing way early than expected. Well, to be exact then even Europe will face a devaluation of its currency but still it would be much more powerful than most other countries of the world. And, for tourists the lower rate of Euro won't create much troubles, and they won't get higher privileges because the value of Euro won't go down in value by a lot.