This is really interesting. It's a post about a job search (from Brent Ozar, PLF)someone did, targeting specific companies and then using LinkedIn and some intelligence to focus their search and get interviews.
It shows that LinkedIn can work well, and that you should try to tailor your search when possible. This is a variation of using a cover letter, but one without the resume. Try to make contacts, and remember the most important quote from the post:
"people hire people".
Get to know people to get the chance at a job.