Hide your Mac OS X username from the login screen. It’s a simply security measure I recommend for people with laptops especially. Here’s a couple of free and easy ways to do it.
TrueCrypt remains to be the best and more trustable cross-platform disk and file encryption system. Here’s how to get it running on Yosemite and any other version of OS X
There’s now a free and open-source way to securely encrypt calls on iPhone, and its cross compatible with Android callers too. It’s easy to install, and easy to use. Free txt messaging is on the way too. Check it out.
Here’s how you can copy and paste long complex passwords into security dialogs (aka. SecurityAgent) on OS X, particularly when creating and opening encrypted disks and disk images.