Killer idea is how to get people to purchase Bitcoin:
1. Without having trust issues. When you exchange bitcoins you don't want to be scammed.
2. Without having banks governments intervene in the process. It should be free flowing, distributed. There should be a million traders all over the world willing to safely trade fiat for Bitcoin - not 10 exchanges around the world that get targeted all the time by banks and governments.
Think a million leaks in a damwall, instead of 5 big leaks.
I think if that happens, it is game on. There are already indications that a good couple of people prefer Bitcoin. People are starting to get the fact that Bitcoin is safer to hold because there is no FactCat at the top diluting your money without any of your control.
We need a mechanism to be able to distribute Bitcoin freely and safely, the rest will get sorted on its own.
The barrier for entry for accepting Bitcoin is low. Create a Bitcoin wallet and you are done. As easy as a FB account was to create when it started.
However to actually get Bitcoins in there is far more of an issue, you have to contact an exchange, KYC, this that. Instead ideally you would want to meet with a Bitcoin dealer, he sets you up and supplies you - if you can trust him.
Bitcoin needs to solve that trust issue, but it is a chicken/egg problem as far as I can see.
There are a million more ways to get some bitcoin in your wallet. Setting up a wallet is easy, then finding someone to fund that wallet with some coins other than buying it with fiat might be tricky, but there are possibilities all around us, the world is your playground and BTC is its currency. Set up a shop, provide a service, do what you like doing and do the best you can and there will be people that are willing to provide you with some currency, not just bitcoin, but it could be and if it happens to be, than you have gained some bitcoin, doing stuff you like doing, it feels so much better than when you just buy them with your fiat money.