You can also roll your own software protection using stand-alone packages such as PGP Whole Disk Encryption.

All these products support a wide range of enterprise-class management tools that let you enforce uniform policies and centrally store encryption keys, including special data-recovery keys that solve the problem of lost passwords and prevent employees from locking employers out of their hard drives.

If you can't do TPM, here's your plan B for encryption

Although the deployment of TPM-based full description is ideal, you may count the cost of full disk encryption and come up short-funded, especially if you just refreshed your enterprise laptops with non-TPM models. Forklifting your entire laptop population is an undeniably expensive proposition, as is replacing the non-TPM laptops if your company has a mix of TPM and non-TPM laptops. If you can't go all TPM, there's a plan B that can give you much of the encryption benefits you need.

You might think that plan B involves partial disk encryption, typically deployed by designating specific folders on a laptop as encrypted; as files are moved into that folder, they are automatically encrypted. Apple and Microsoft have long offered this form of encryption, via FileVault on the Mac and the Encrypted File System tools in Windows XP and Vista. But this approach has a major flaw: It depends on users to properly store sensitive data only in encrypted form.