It depends on the sophistication of the attacker. If you have TrueCrypt installed and a big chunk of random data on your disk then it's pretty obvious that you'

It depends on the sophistication of the attacker. If you have TrueCrypt installed and a big chunk of random data on your disk then it's pretty obvious that you're hiding something. Even stenography is pretty easy to detect for non-trivial amounts of data. Another issue is that you never know if the border patrol is going to add some unwanted monitoring software or hardware to your computer. It seems unlikely but with the NSA revelations we had I wouldn't be surprised anymore.