Maybe the solution is to have a first "primary" partition, then an "under duress" partition which you'll fight tooth and nail to protect, filing every appeal possible... and if you finally do give up the key, it's filled with entirely legal but extremely embarrassing pornography, plus a few self-written Harry Potter fanfictions.

Meanwhile, whatever you're ACTUALLY trying to hide is on a third.

Sure, it's a big damn hassle, but if you're conscious enough about the stuff you're trying to hide to go with a TrueCrypt hidden volume, it'll be worth your effort.

(I'm not actually sure this is possible, but if it is, I'm sure someone else has come up with it already.)