Jungle-search.com makes it easy to find free Kindle books.

Companies with their own Kindle competitors, such as Barnes & Noble, Sony, and Apple, make a big deal of the fact that their e-book readers are compatible with the ePub file format. That means, unlike the Kindle, that the Apple iPad (through various apps, including iBooks), Sony Reader, and Barnes & Noble Nook can be used to read tens of thousands of free books from Google and a variety of other sources. Just choose a title, download the ePub version, and transfer it to the compatible reader of your choice. Yes, nearly all of the books and essays in question are public domain classics (and sometimes not-so-classics) of yesteryear--the works of authors such as Arthur Conan Doyle, Jules Verne, Mark Twain, William Shakespeare, Jane Austen, and the like. But free's free, and these are the sort of canonical works of art that bookworms appreciate reading and re-reading ad infinitum.

But fear not, Kindle owners: you too have access to many of the same public domain titles, numbering in the thousands. Amazon has made it easier to find them than in the past by displaying the paid and free titles in the top 100 list in adjacent columns (overall and by genre). But what if you want to see more granular lists--say, separating the public domain titles from the modern freebies (Publishers occasionally give away older books in a series to hook readers on newer ones, for example.) Or what if you want to see only books in a certain price range--only those that are 99 cents, or $2 to $3

That's where Jungle-search.com comes in. The search engine is designed to scour Amazon for all sorts of deals across a variety of categories. And that includes Kindle titles, which can be filtered by price. As of today, there are almost 17,000 free Kindle titles (see links below). Nearly all of them are public domain titles, including many of the same you'll find on Google Books. The remaining 246 free titles tend to be Kindle games, or those aforementioned freebie promotional titles. Currently, it looks like romance titles dominate the top of the list, but you'll find plenty of thrillers, and even some "Star Wars" books in there, too. (These titles tend to turn over pretty quickly, so it's worth checking every few weeks or so.)

The price searches on Jungle-search are customizable, so you can also use it to search for bargain Kindle titles as well. For instance, you can currently find more than 220,000 titles available for under a buck, and more than 125,000 costing between $1 and $5 (including megahit "The Girl with the Dragon Tattoo"). Just remember to filter out the magazines and newspapers that sometimes come up in such searches, since they'll bill you on a weekly or monthly basis.

Kindle titles by price (via Jungle-search.com as of December 29): Free Kindle e-books (public domain): 16,528 Free Kindle e-books (non-public domain): 246 Kindle e-books ($0.01-$0.99): 83,902 Kindle e-books ($1.00-$4.99): 216,986 Kindle e-books ($5.00-$7.99): 257,493 Kindle e-books ($8.00-$9.99): 125,975 Kindle e-books ($10+): 127,346

Remember, even if you don't own a Kindle, you can still enjoy the e-books--free or otherwise--using the various apps (Kindle, Nook, Kobo, and so forth) available for iOS, Android, and BlackBerry devices and phones, as well as on Windows PCs, and Macs.

Got a favorite free Kindle title Or another source of free titles Share your finds in the comments below.

Editor's note: This post has been updated since its original publication with additional information.