Buy to Let
Mortgage providers' traditionally only offered loans for people buying homes. An increasing number are offering loans for a property you want to "buy to let", (i.e. not to live in as your home, but to rent/let out to tenants).
Getting income from the rent is seen as a good investment by some and is becoming more commonplace.
It's particularly popular for retirement planning because of the growing concerns about the inadequacies of traditional pensions. The old saying "There's nothing more solid than bricks and mortar" is more relevant than ever.
The fears over the past couple of years that the market was saturated seem to have been incorrect. However make sure that your buy to let property is in an area which is likely to have a demand.
There is a wealth of information on buying property to let. Just make sure if you're paying for it that it's been written by someone with direct experience in the field.
Buy to let mortgages are not regulated by the Financial Services Authority.