How do i change the trackball color on my bb pearl?

ok so i know theres an application but i want it to change colors like a sidekick. rather then just sit there as one color. like when i get a text it should flash colors and same with a phone call. does any one know where i can get that application or software for free?How do i change the trackball color on my bb pearl?Try to add more details to your question.

Duvet sets for toddler beds

wireless mouse