Free Wi-Fi is so easy. You pull out your smartphone or laptop rental and up pops a number of Wi-Fi networks to connect with. No security keys to enter or charges to be incurred. So what is wrong with this picture? The truth: Just about everything. It turns out that hackers and scammers lurk in places where business travelers and attendees reside - hotel lobbies, trade show floors and airports. Most attendees have just gotten off a multi-hour plane ride, landed ground transportation...