As for cell phone and Ipod headphones since they can be carried they might be considered dangerous as they tend to take your mind to other places and you have to be very careful where you walk.And if you're not careful they can negatively effect your hearing. But this would be a fault on your part.
[Edited by AdmiralAckbar, 5/31/2010 1:04:08 PM]
Yet I always end up using my crappy 2.1 speakers.
I spent over $100 for my audiophile headphones from Sennheiser.
Sennheiser HD 700's? Because they are the balls.
I'd say headphones over speakers in any scenario except a party.