One thing that has been bugging me on my blackberry is the way it showed SMS and email in the same inbox. I’ve missed quite a few SMS messages because of this. Anyway, it turns out if you go into the combined inbox, hit the BB key and select options, you can tell it to separate them.
Blackberry Example App
If you are looking for good example application on the Blackberry, checkout the WordPress Blackberry app. It is open source so you can easily get the code and it does everything from resizing images to keeping an offline synced copy of data to making server connections and accessing the GPS.