Swoosh: "With a password with 100 chars/numbers it would take approx 115 years."
Although it could take approx 115 years, that figure is most likely based on one machine not a cluster working in harmony. So I wouldn't get to comfortable.
Nihil: "... given time, nothing is secure."
Swoosh, you're probably already thinking about it however it hasn't been mentioned yet; in order to make it as discouraging as possible for the deviant that's trying to crack your passwords, regardless of the complexity of the passward, change them frequently. Any progress they may have made is null and void at that point, he/she will have to start all over again. If the password is that hard to get around, where's he hiding the logs! That in itself may persuade them to look for an easier target.

$.02

cheers