wow thats alot.
NOTE: My math may be wrong!
Well if my computer can check 200,000,000/Sec then thats 17 trillion addresses per day.
Lets see how close I can get to guessing a private key.
addresses per sec * seconds * minutes * hours * days in the year * age of Earth * some other number to get us close to guessing all possible combinations.
200000000*60*60*24*365*4500000000*10000000000000000000000 = 2.8 x 10^47 (close to how many possible combinations would have to be checked (I think))
So my computer would have to run constantly for the age of the Earth times 10 thousand billion billion (note that about 3 times is already older than the known universe)
So my computer would be running past the heat death of this universe and probably still would have not guessed a key with a balance.