A 'launchd' plist to automatically lock your Mac as soon as you log in.

com.tjluoma.autolock-on-login.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>Label</key>
	<string>com.tjluoma.autolock-on-login</string>
	<key>ProgramArguments</key>
	<array>
		<string>/System/Library/CoreServices/Menu Extras/user.menu/Contents/Resources/CGSession</string>
		<string>-suspend</string>
	</array>
	<key>RunAtLoad</key>
	<true/>
</dict>
</plist>