At current amount of Ripple, somewhere between 50 and 100 $$$ is possible under some circumstances.
However, transactions will use transaction fee, and that will burn ripple, lowering circulating amount,
which should lead to deflation and price increase.

However, I (and probably not many people here) can't predict at what rate will XRPs get burned,
as theres too many variables in the system

So if you buy 1000 XRP now, and hodl up to year 2050, maybe you'll be billionaire, who knows