Several times each year, I receive unsolicited introductions from tech recruiters, usually via LinkedIn and usually local firms. I am not currently looking for a new job.

Is it advisable to establish a relationship with one or more recruiters when I'm not interested in finding new work, so that they have my resume on file?

Here's another way I approach the question: My plumber was first hired at the point of need: I had a plumbing problem, looked up a few of them, and evaluated and hired based on their demeanor and cost estimates. I established a relationship with a general attorney, on the other hand, well in advance of ever actually needing services so that if or when services are needed he already knows enough about me to begin work. Should I approach recruiters like I approached my plumber or my lawyer?

A separate discussion, I suppose, is whether or not the type of recruiters who troll LinkedIn for clients are generally helpful or not.

Edit: I have never worked with a recruiter before, and therefore have little idea what to expect.