Well, Sensible Sam, you should also consider getting an external drive and using Time Machine to back up
all of your data, just in case.
It does such a fine job at backing up, somebody could swap my MacBook Pro out with a brand new one, restore from a Time Machine backup and I'd be none-the-wiser.
As well, don't make the same mistake as 99% of my customers. Change your Account preferences so that your Mac does
not automatically log in. If it's that easy to access your information, you may as well pass it around the class and give everybody a peak at those naughty movies you don't want mommy to see.
Just saying
As well, if you're really paranoid, you can create a sort of "virtual hard drive" that is password protected and would take
years for the world's most powerful computers and clusters to crack, at
least. Now that's a secure place to store all of those pictures of naked cats
If you want to know how, visit my blog [in my signature] and I'll have a how-to up by tomorrow!