I just read on the Barnes & Noble forum that Kaplan is listing 130 ebooks for free until January 10th. Most of the titles are academic or career-related, but I found quite a few good ones in there. You can either download them free from B&N, or go to Kaplan's free ebooks website.
I recommend erring on the side of caution, and downloading every ebook you think you might be interested in, whether you want to read it now or not. Since they are only free for a short time, you might as well get them while it doesn't cost you anything — you can always delete or archive the book later on if you change your mind!