Just got some 50 or so free PLR articles for use.
When I initially thought to use these to get some fast articles posted, I remembered the warning: if the managers for these article directories find you are submitting duplicate articles, they will delete those articles - and if you submit too many, they delete your account.
I looked over the articles and found, however that they were fairly well written, true for the most part (and easy to edit where not), and all organized into files by subject.
Inspiration hit - I just had a free ebook on my hands - a free special report! In fact, I had several of them. All I had to do was to import them into OpenOffice and export them as PDF once I had formatted them for easy on-screen reading.
Voila! Now I have a half-dozen freebies to give away or in exchange for email addresses. Since I "own" the rights to these, my creating ebooks out of these is also legal. When I add my own introduction and bio, as well as ads for my other products in the end papers, this creates a new work. If I still had any doubt about my copyright legitimacy, I'd add in my own articles in the same area - or an excerpt from one of my books, such that the PLR articles now didn't compose the bulk of the ebook.
But the best defense if giving them away for free. I got them for nothing more than my own email address. All I get from giving them away as ebooks is more email addresses. If someone ever complained, I'd simply pull them from distribution. (Interestingly, as I continue to write my own articles in this area - and these articles are part of that research - I'll be able to replace those articles with my own, and title it the same. That saves re-linking and so on.)
So there is a great use for PLR articles, particularly where you have bought or earned the right to them. Check any fine print that comes with them - but go ahead and make them earn you captured email addresses, as your own special reports.