If your data isn’t immediately accessible online, either behind your firewall or behind someone else’s firewall or in the cloud, when your employees need it, then they are going to download it to their machines. If their machine is a laptop, and the data is not securely encrypted, and the laptop is stolen, then, as per a ZoneAlarm Blog Entry on “what is the cost of a missing laptop” from earlier this year, it could cost your organization 1 Million (or more). (And even if the data is encrypted, and it’s valuable enough, someone will invest the time in breaking the encryption.)
But if your data is always available, and, better yet, the applications that do the processing reside on the servers the data is on, then your employees and contractors won’t need to download it to their laptops to process it. And you can even implement safeguards to prevent such. Then, when the laptop gets stolen, your loss will be the replacement cost and a minimal lost productivity cost (as you can replace it in hours), which will max out at a few thousand. Compare this to the situation where you have data breaches, IP loss, and forensics and investigation costs which can be 10, 100, or even 1000 times the replacement and lost productivity costs.
So encrypt your data, put it on a VPN behind a firewall, and make it available 24/7. It will be much cheaper, and safer, than having it unencrpyted on your employees’ laptops which will, inevitably, get stolen despite their best efforts to protect them.