Have a look here for more details on how many complications for address could ever exist:
https://bitcointalksearch.org/topic/how-many-possibly-bitcoin-addresses-are-there-exactly-and-how-long-does-it-24268
But to summarize, 2^160, means that there are so many that even if every computer in this earth was using its max power to create addresses it would take ages to create all the possible complications. You could also create vanity addresses that would look like 1Gay....
It is interesting to research how BTC Addresses came to be.. I just found it hilarious that I was assigned that address....
Cheers!
The 1JAsFKGAYup n00b