If you already use Audible for audiobooks, you now have a new perk in your account: Access to three fitness programs from Aaptiv, with more in the works.

If there's an area in your life that could do with some improvement, a good audio book might be able to steer you in the right direction. Best of all, they can be readily absorbed while driving or multitasking, which makes them perfect for people with busy schedules (i.e. - nearly all of us.) We asked Amazon's digital audiobook arm Audible to share some of its best-selling self-improvement titles. Here are their picks.

Audible is the biggest name in audiobooks, but even if you've spent hundreds of hours listening, there are some tricks hidden beneath the surface. Here are some of the best ways to get the most of your Audible experience and even save some money in the process.

Amazon currently sells audio adapters that enable visually impaired Kindle owners can have their audiobooks read aloud to them. Normally, this adaptor costs around $US20 ($28), but you can make your own for as little as half that.

Spotify is essential for music lovers, but it's got a lot more to offer than good tunes. You can stream audiobooks, radio dramas, language lessons, famous speeches and more for free.

iOS: The DRM-free audiobook business isn't exactly booming (though sites like Downpour and LibriVox are out there to help you find some), but that doesn't mean you might not have audiobook files sitting in your Dropbox account. If you do, Bound is a great player.

Shelfie, formerly known as BitLit, already lets you take a photo of the physical books you own and get matching ebook copies. Now they're throwing audiobooks into the mix, so you can listen to the books on your bookshelf too.

There's a lot of benefit to reading regularly, but it can take a while to get through a book. To speed up the process, try listening to an audiobook simultaneously, at twice the speed.

If you're looking for ways to fit more books into your life, listening to audiobooks is a great way to do it. You can listen on your commute, on holidays, or at home while you're doing other things. This week, we're looking at five of the best audiobook services, based on your nominations.

The internet is full of brilliant articles you haven't read. So is your read-it-later app of choice, whether it's Pocket, Readability, Instapaper or any other. Here's how to finally tackle that reading list, with a little help from technology.

Dear Lifehacker, Over the years I've collected hundreds of books I want to read, but no matter what I do they just keep piling up. Is there a way I can read faster and get through this backlog quickly?

iOS: Audiobooks are great, but they're generally pretty expensive. Fortunately there are a ton of free audiobook recordings in the public domain, and now you can easily download them to your iPhone, iPad or iPod Touch.

Android: Quietly rolled out for public testing, audiobook service Audible has a free beta of its Android app that some users have been describing as the last iPhone-to-Android gap. As you'd expect, it downloads, plays and maintains your audiobook collection.

There are loads of free audio and e-books available online for the taking, but tracking them down across their many sources can be tough. Web-based search tool Librophile makes the job a lot easier.

iTunes 8 has added simple under-the-radar feature that allows you to quickly and easily tag any file in your iTunes library as an audiobook and move it into the Audiobooks section of iTunes and your iPod. The simple trick? Just right-click a track and select Get Info, head to the Options tab, and then select Audiobook from the Media Kind drop-down menu. The file will instantly leave your Music library and head straight for your Audiobook library. To mark multiple files at once, just select them all and go through the same process. The only remaining step is to tick the Remember Position checkbox if you haven't already, and your tracks should now have easily found their way to your Audiobooks section, and even better, they should work like an audiobook. Finally. Thanks Brett!