Full disk encryption: Key on USB storage device

[Jens Müller]

I want to encrypt my Netbooks HDD.

If I understand 
http://kuparinen.org/martti/comp/ubuntu/en/cryptolvm.html correctly, 
that is possible with the Alternate install CD.

But what I miss: Is it possible to put the key file onto a USB stick so 
that it is loaded automatically from there at boot time? Long time ago, 
I looked at the Gentoo initrd script, which apparently supports this.

A bit more sophisticated: Is it possible to put the whole boot partition 
including the key file onto a USB drive?

I also found https://wiki.ubuntu.com/SmartCardLUKSDiskEncryption, which 
sounds nice. Are there such smartcards in the form of a self-contained 
USB device which I can put on my keyring?

Thanks,

Jens