As a Professional Real Estate Virtual Assistant, I look high and low for free or low cost productivity tools for my clients.
Fidelity Assets My Client Builder: http://www.fidelityassets.com/ is another one of these tools.
In their words: "My Client Builder is a custom built publishing platform, or blog, that is designed to help you, the real estate professional, grow your sphere of influence by communicating with home buyers and sellers who are actively searching for real estate on the Internet. When a home buyer or seller arrives on your blog from any of the traffic sources discussed below, lead capture forms and an email subscription form help you capture more leads so you can effectively and efficiently build your online community"
You can add your listings with photos and syndicate to various sites which should generate traffic for your website and give more exposure to your listings.
If visitors enter their contact info, it will be added to the built in e-mail manager, and your website/blog is updated daily with real estate news stories.
Of course, there are plenty of fee based marketing services available.
I am going to sign up one of my clients tomorrow. We'll see how it goes. Can't beat free :-)