I also have a question regarding the practice of multiple domains pointed towards one site.
I have a relatively new domain (www.goodies.no) but the services provided through that site will be very varied (think web design, app development, marketing and SEO services etc)
So my theory was that in addition to creating www.goodies.no/webdesign folders for the webdesign service, I should also set up a www.goodies-webdesign.no domain pointing towards that same folder.
Does that make any sense at all, I though maybe having a vital keyword in the domain name would be beneficial to my SEO as long as the contents of the www.goodies.no/webdesign site it links to is highly relevant to the domain name