steady income in btc i think not too difficult, if you do in mining, i think that's "whitout actively doing anything"
If you can build a exchange like bitcoin to paypal and paypal to bitcoin it can many more people that can exchange to your site with low fee than virwox..
It is not a bad thing if a person wants to aim something higher and this is good to consider to build your own exchange site and compete to other popular ones. But before you can get steady income from it, you need to have a good marketing plan to let the people know that you have an exchange site that it better than the old ones.
The main thing you need is money or capital and everything will just follow.........
Money is not the only factor to consider for success, the most important is to have the motivation and the vision for what you want to accomplish. Without them, I think even is you have all the money in the world, you can't create an exchange or anything you have in your mind.
But, if you success to implement your exchange, for sure you can create an income for yourself.
This will make you work harder and aim higher if you do have those type of attitude and having money for investing into an exchange is not just enough. And you can't just pay a person to operate your own business without supervision, that is what motivation and vision will help you to achieve this type of goals in able generate steady income.