Another good option is to take a 32-gig SD card, and re-label it as a 1 gig. Then fill the card with random output, reset the number of cylinders in Fdisk to match 1 gig, format a 1 gig partition and fill it with pictures of scenery. Put you encrypted data at some point after 1 gig on the raw device. To anyone looking at it casually, it will appear to be just a 1 gig card. Even if they see the empty space afterwards, with good encryption it should be indistinguishable from random noise.
Bonus points for modifying the firmware on the SD card so that it looks like 1 gig at the low level.
They don't use the forensic tools on everything that passes through, and an SD card full of landscape photos is a lot less likely to arouse suspicion than one full of unreadable encrypted data.
Bonus points for modifying the firmware on the SD card so that it looks like 1 gig at the low level.