Blackberries are so addictive they are referred to as Crackberries. 
Case and point: while flying down from Seattle I was sitting next to a guy 
who was pounding away on his Blackberry as we descended. Every few 
seconds he would look up and down the aisle to make sure the attendant wasn't 
coming. Once the coast was clear he would go back to typing away. 

Hello...you shouldn't be worried about getting busted by the attendant! 
You should be worried about sending the plane into a tailspin. Go to 
rehab and kick the Crackberry habit. 

Full disclosure: I wrote this while flying at 10,000 feet, but made 
sure to shut the wireless component of my Blackberry off. After all, I'm a 
recovering Crackberrier myself.