Most of us use wireless networks at home and when we travel. The other day I was sitting in an airport waiting on my late flight (that of course never happens), and I fired up my laptop to get at a few emails over the local Wi-Fi hotspot. I was responding to a few items and sent a couple of spreadsheets and documents.
I sent a proposal to a colleague for input before sending it to a customer. The document had pricing and other confidential information in it. Since I was on an open wireless network, a hacker with a Pringles can as an antenna could steal my file. Talk about scary. If I log into my company through a VPN that encrypts my traffic, I should be safe. I was using GMail, so I may be compromised.
Fortunately I encrypted the file using an enterprise digital rights tool that made sure only my colleague could see it. If that hacker with the Pringles can grabbed my file, all they see is garbage. A little prevention saved me a lot of possible headaches later.