How far does encryption get you?

Finally, since a short while, all my hard disks are setup to use encrypted disks using LUKS. Works like a charm and you don't really notice it slow down. Unfortunately I am now left wondering what the point is, given that I currently live in the UK. Not that there is anything exciting on my hard disks, but I'm one of these people who care about principles regarding freedom.

One possible thing to do is create a key on a USB stick instead of using a password. It would mean I can destroy it when they ask for it as it seems they have to ask you by letter first. Although I can't imagine a situation where I'd rather lose all my data myself too then have the police poke their nose in it.

At some level I can't help but compare them (the UK government) with the music and video industry: create new (broken) laws as they are unwilling to adapt to innovations.