Either as a discreet part of your website or as the main componant. Its possible to add a complex searchable directory system to your website. Your directory could list internal products or services, or external websites etc. Your users can enter and manage there own entries, either on a free submission basis or a paid submission basis. It's up to you!
For an example of a simple, yet powerful online directory, take a look at www.PhotoStudiosForHire.com Instanfruit was able to create a simple online directory system with users able to register and create and manage directory listings for their Photographic Studios! People searching for studios to hire can use the in-built search tools or browse the directory by country and region.
Simple!
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