4) BlackBerry microSD Memory Cards

Memory cards are essential if you want to use your BlackBerry for listening to music or viewing video; the miniscule amount of storage space built into your BlackBerry's internal memory makes it less-than-ideal for keeping and consuming multimedia.

SanDisk 4GB microSD Memory Card

Luckily, compatible memory cards are relatively affordable, especially if you only need a small amount of storage. Amazon's currently selling 4GB cards for as little as $6; 8GB cards are listed for $14; and 16GB go for about $46.

BlackBerry smartphones running OS4.6 or higher support microSD cards up to 32GB.

Read "BlackBerry How To: Insert, Format and Use microSD Memory Cards," for more on memory cards and RIM smartphones.

5) BlackBerry Headsets and Earbuds

A good headset or pair of earbuds is a necessity if you want to realize the true potential of your BlackBerry smartphone. RIM makes its own phones, and its high-end headset is a great option for anyone looking to use the headphones solely with BlackBerry devices. That's because the product has a multimedia "controller" built into its cord that only fully works with BlackBerry devices.

(Read my full review of RIM's BlackBerry Premium Multimedia Headset.)

RIM BlackBerry Premium Multimedia Headset

For the purposes of this article, I'm focusing on headsets and earbuds, since they're more mobility-focused than headphones.

The quality of the BlackBerry Premium Multimedia Headset, which can also be used to place hands-free calls, isn't great, and serious audiophiles might be a bit let down. But it's significantly cheaper than additional high-end alternatives. RIM sells the headset for $90, but you can pick it up for half that price at CrackBerry.com.

Beats by Dre earbuds and headsets from V-Moda are also viable options for folks serious about their music, but they're both significantly more pricey than RIM's options at $150 and $95 respectively on Amazon.