If you've jailbroken or unlocked your iPhone, iPod, or iPad before you're probably used to the usual procedure. You usually have to download the iOS IPSW firmware file in order to continue with the jailbreaking of your iDevice.
ipswDownloader by developer Vitaly Parovishnik makes this process a whole lot easier. The program not only downloads the IPSW firmware file for you, but also displays whether the firmware you've selected can be jailbroken and unlocked, along with the size of the IPSW and the tools needed to jailbreak the firmware.