I suppose the short answer to that question is - they all do. Some require more expertise than others - some require investment of money, others investment of time and yet others require both time and money. Most also need good advisors.

For someone with a lot of cash and no real interest or time, term investment with a fixed interest rate may make sense. Returns on this vary greatly so best to do your homework on best interest - do watch out for the small print though so you don’t get stung with high management fees.
If you love scanning stock markets and have a good grasp of how it all works, plus a few inside friends who can help you to get in early on markets - that could well be a very lucrative investment proposition for you. You can also go through a stockbroker who will invest money for you. As with a lot of ways of making money you will need some capital or equity in something to get started. The more you invest the more widespread and stable your portfolio is likely to be.

Investment property also requires capital and some knowledge of the property market. If you have the time to go out yourself and look for properties which have a good chance of appreciating well either long or short term, this may be the bricks and mortar venture that appeals to you. There are also companies who will find property for you, usually for a percentage on top of what you pay for the places themselves. From the point of view of tax incentives and negative gearing property may be the best bet but even then you need to have a competitive enough mortgage rate to make the whole prospect viable.

You may decide that a government housing scheme sounds the most stable and steady course. Most state governments have housing projects in which you can invest - ask your local council for details.

Other investment opportunities include buying fine art to be then rented out to clients wishing to decorate their office space. You will again need quite a lot of capital to do this but if you are an antiques or fine art fancier this may well appeal as a way to finance your hobby and increase your collection.

You can invest in your own business - if you have enough money available you can buy a franchise with one of the big companies. There are some excellent business systems which include real estate, stock and all the training necessary to make your efforts guaranteed to succeed. If money is not as easy to come by you could invest in your own ideas - be careful to research the market and make sure that there is room for such an innovative step - remember that only one of of five small businesses are still in existence after two years - meaning a lot of time and money wasted. A third option would be to follow one of the many systems available to build passive income. Usually the financial outlay for these is not exorbitant and with companies that have been in business for more than 10 years there is training and support both online and one-on-one to help you succeed. Working for yourself can be incredibly rewarding while demanding a lot of your time when you are starting out.

Whatever financial backing you have available there are usually many options. As with so much research in this day and age, the web is a fabulous source of information and advice.