Using mobile digital devices--iPods, personal digital assistants (PDAs), Tablet PCs or advanced cell phones--is becoming a big campus trend. Their advantages include convenience and the ability to hear lectures or course-related music just about anywhere. PDA's such as Palm Pilots and BlackBerrys, iPods such as Apple's and Tablet PCs, including ones made by Hewlett-Packard, all provide ways for busy students to carry a lot of information wherever they go. PDAs allow students to communicate with each other and their teachers, making it easy to work on joint projects. Tiny iPods can download great quantities of data. More expensive Tablet PCs offer many attributes of laptops and can easily integrate into university wireless communities. Even so, there are significant obstacles to overcome. Some of the mobile devices, notably PDAs, are too small to be easily used and some universities don't have the information technology infrastructure to handle them. The biggest impediment is money. Each mobile device costs at least a few hundred dollars each, while top-quality Tablet PCs run over $1,700 apiece. There are other costs involving infrastructure upgrades, as well.