Isn't it theoretically possible to crack the hash of existing bitcoins to "recover" (or rather forge) them?
The odds of that happening are less than the odds that you will die from being struck by lightning after being hit by a meteor which occurred just after you had been bitten by a shark while you stood underneath the curl of an approaching Tsunami -- and all that happening 1,000 times in a row on the same day.
Easy there. There are only 160 bits in an address. I don't know what are the probabilities for these events but let's say lightning is 20 bits, meteor 30, shark 15 and tsunami 20, and that they're all independent - you've already used up 85 bits. Having that happen 1000 times puts you at 85000 bits which is way too much.