While you should attempt to maximize the potential of each business, you should start by spreading your income base quickly by setting up 4-5 small online businesses and focus on maximizing them later. With public domain, this approach is quite easy and is very successful.

You can pick several public domain works, create different products for each of them and after you have set up their individual websites, return to improve and diversify each website. This will allow you to both generate multiple income streams and then maximize the income potential of each stream within a short period of time.

So many people think of the public domain for starting a new business that they forget the strongest benefit of using the public domain – instant content. If you already have a business that can use supplementary content – search the public domain for possible content. Not only can such new content be used to increase your AdSense income but it can also 'sell' your other products and services by building your business reputation as an expert.

Of course, it's not always possible to find relevant content (information on the latest microprocessor technology is unlikely to be in the public domain), but there are many niches (dream interpretation is just one example) that have more or less timeless appeal.

If you operate a business that works in 'timeless' niches, the public domain can become a far better resource than any ghostwriter you can ever hire!

In any Internet Marketing basics course, the point is made time and time again that you should choose your first business from within your own interests. Logic says that people share hobbies and interests, and if there are enough people like you searching for information on these interests, you stand to make some serious money.

This advice is both good and bad. While it is helpful to start a first business in a niche that is your interest, it's often the case that these niches are not very profitable – there might be too much competition or not enough demand (or just not a 'buying' market).

On the other hand, hobbies such as bowling, playing poker, crochet patterns or even architecture are excellent avenues for starting small public-domain-supported business sites. By using public domain works that outline everything from playing tips to history and immediately usable information (recipes for chocolate chip cookies, anyone?), you can carve your own little niche and not only build yet another income stream, but enjoy yourself while doing it as well.

The point is that you should assess your current resources – your business and your hobbies – to see how the public domain can bring in new income for you.