Since today, koopjeszoeker.be (and koopjeszoeker.com, fr.zamtam.be and www.zamtam.fr) supports Google rich snippets. Not much happens yet, but you can have a look at the parsed data in this testing tool.
At the moment I still get “Insufficient data to generate the preview” from this tool although it seams to be able to parse the data, no idea what it means…