Here are a couple of free Blackberry downloads.. besides the already popular Instant Messenger.. these are a couple new ones that you might now already know about..
Weatherbug – It updates itself to local weather conditions in the weather in a set location. For example, when it is partially cloudy, your WeatherBug displays an image of the sun with a cloud eclipsing it, as well as the current temperature and the days highs & lows. 
Viigo RSS Feeds - Easily scroll through stories & move from left to right from older to newer
Facebook – See status updates, write on friends walls, etc
Flickr- Take pictures on your phone & have them instantly updated on your Flickr site…
WorldMate Live – includes my itinerary which includes information on flight, hotel, meeting, car rentals etc.. Read hotel reviews, maps and current date & time of traveled city.
Opera Mini - Can you ever really have too many browsers?
Of course there is Blackberry Media Sync if you are looking to add music to your Blackberry.. but it really cannot compare iphone’s Shazam that listens to the music as you hear it in the background & tells you the songs name, who sings it & you can add it to your itunes… very cool.
