Rumor has it that when Satoshi returns he will give all forum users 1 BTC for each merit they have 
This is why you should always have a BTC address in your profile.
This is just a rumor, after all Satoshi never promised publicly to give 1 BTC to all forum users based on their achievements. I think if he gave 1 BTC to all forum users based on calculations that are still active or frequently involved in discussions on the forum, that would be a lot of BTC that Satoshi would have to spend for that.This is why you should always have a BTC address in your profile.
He once made a post as quoted by @dzungmobile, but he didn't mention anything more specifically there. I don't take this rumor too seriously, but I also couldn't resist 1 BTC from it.