The lid (or how we call it, 'hard protective cover') is unique for all competing e-readers... I haven't seen any other e-reader with such a cover. It is very hard and durable and so far (knock3thewood) nobody ventured to break it)
here is one more nice review of PB 360:
http://www.walyou.com/blog/2010/01/2...-360-e-reader/