Not meaning to be a jackass but realize that maybe if you downloaded (and maybe already deleted!) that porn video with that girl that might or not might be 18 you could be in big troubles if you don't have your full disk encrypted. Edit: or other things that would be ok but can be used against you by law enforcement, for example what about your collection of pirated MP3s or DivX? Is this more acceptable than accident…
An encrypted disk could also get you in a position where you have to give up your password. Be careful with your porn-filled encrypted hard drive.
Fortunately that is not my case but I can't say I don't have any MP3s of DivXs that aren't, err, properly licensed.
Edit: or cracked software, we have very high fines in Italy for using softwares without a license.
I'm just saying that in case the police have a look to your laptop and they WANT you to charge with something, they will.