What can you do that is illegal on sites like LimeWire?

You can't do anything illegal directly on the Limewire website. You would have to download their program, Limewire. This program will let you (among many other things) download copywritten files illegally and share them with other people. If you don't share copywritten files, you can't get caught. And even if you do share, your chances of winning the lottery are better than your chances of getting caught. -DJ Craig