If you like themes, you can download Plazmic theme creator from [ plazmic ]
and make your own themes, or you can find several free ones, or you can find them for purchase at various sites.
As for apps, I really like BerryWeather, and BerryBuzz. There is also CaptureIt which will take screen shots directly from the device. I also like MaraTick, which is a really cool grocery list type of program. I like it because I get to use my BB while grocery shopping, so the wife never knows if I am texting or checking stuff off the list.