The following post will show how in one of the projects that I took part in we used Spring's AOP to introduce some security related functionalities. The concept was such that in order for the user to see some UI components he needed to have a certain level of security privillages.
A large portion of the design world and folks inside Apple are not fans of Skeumorphism in the modern age. Sure it made sense 30 years ago but consensus is now that these skeuomorphs are tacky, obtrusive and make the company look dated and behind the times. Many feel it disables innovation.