Solution : truecrypt http
/www.truecrypt.org/ it is free and you are not required to give up the password
Back up your entire hard drive and keep the backup at home
on the storage you are taking with you, perform whole disk encryption
use at least a 20 character long password it can even be a simple statement or saying that you can remember. because of the characteristics of truecrypt, each attempt of a brute force requires a large portion of the file to be read before the key provided can be seen as a hit or miss because of this, the brute force process is significantly slowed compared to just trying to break a hash
so encrypt and answer no. No government has the time or resources to try to break a high level encryption in order to see if you were lying about having porn or not unless it is of national security.
And if you really feel like being a jerk, you can also keep your porn in a encrypted volume then for OS, have that partition unencrypted then set your background as a image of some nasty stuff thats not porn. Have a lot of people load up a package of really nasty non porn images then when the drives are checked for porn, the workers will be constantly grossed out and will eventually protest being required to look at peoples storage.