Good Domain Real Estate - No Idea

I have a number of quality keyword variation domains for my local service business. I have my main site and I am using one domain as a separate blog. Does anyone have an idea on what I should do with the others?

Do I create blogs on different servers or can I put them all on one server or should I just create a single landing page of sorts with some info and a link to our main site? I'm not an seo so any help would be appreciated.