Over the past weeks and months, I've worked hard to deliver to you the best free BlackBerry applications the Internet has to offer. I dug up my top picks for free open source BlackBerry apps, the best mobile Twitter apps, and the highest quality BlackBerry Storm software. I even asked RIM's co-CEO and two additional executives for their favorite free BlackBerry software, then delivered the answers directly to you.

This time around, I picked a handful of new apps that promise to vastly improve your BlackBerry's audio experience, help you rapidly browse the Web, manage your online DVD mailing account, find just about anything from anywhere, and even grab screen captures of your device's display without the need for a PC.

Slacker Radio for BlackBerry: Your New Radio is...Your BlackBerry!?!

It's rare, but every once and a while a new BlackBerry application comes along and single-handedly raises the bar for all other mobile apps. The last such piece of software I can remember to fit this description is Viigo, the ultimate mobile RSS reader and lifestyle app. For a long time, Viigo has been my favorite free BlackBerry app, but today, thanks to Slacker Radio for BlackBerry, I'm just not sure anymore.

Slacker Radio Home Screen on BlackBerry

Slacker Radio for BlackBerry is an easy to use, personal Internet radio app that brings unlimited free music to your RIM smartphone. More than 100 pre-programmed "genre stations" let you listen to a variety of artists and ensembles for as long as you want--or your battery lasts. And the app works well on just about any BlackBerry device running RIM's handheld OS v4.3 or higher and with at least an EDGE or another 2.5G data connection. The app also works over Wi-Fi. (For best results, employ Slacker for BlackBerry on a device running BlackBerry OS 4.5 or higher.)

The best thing about Slacker for BlackBerry? Why, it's free of course--or at least there's a free option. To employ the new app, simply surf on over to Slacker.com using your BlackBerry browser and follow the on-screen download instructions. Once the app's installed, you can either log in to an existing Slacker account or create a new one. You'll have two options for account creation: 1) a free account, which delivers the occasional audio and visual advertisements and lets you skip over songs just six times an hour; and 2) the commercial version, which is available via subscription for $3.99 a month--$47.88 a year--and doesn't have a limit for song skips or requests.

Slacker Radio on the BlackBerry Bold

And though Slacker mobile also works on the iPhone and iPod touch, one of its most valuable features is currently restricted to the BlackBerry-specific version: station "caching." The ability to cache, or store, Slacker stations on your BlackBerry's media card means that you can listen to your favorite tunes without wireless connectivity, which makes the app particularly well suited for use during travel. (You must have at least 500MB of free space on your media card to cache Slacker stations.)

And like most BlackBerry apps, it supports multitasking, so you can, say, play a game of BrickBreaker while jamming out to the Beatles on Slacker.

More details on Slacker Radio for BlackBerry can be found online.