My opinion is that you should only bring a water bottle and plenty of snacks on board (Bits & Bites being my favorites!). Some good reading material is a good must, and your favorite headphones along with an airline plug adapter for it to work in stereo.

In other words, don't bother too too much about the on-board part. As for checked baggage, I think you can put pretty much anything in there, other than firearms and explosive devices.

I would probably chuck your main PSK into your checked baggage. You will probably have some leftover water (from your bottle) when you land, and by the time you're leaving the baggage carrousel, you'll be reunited with your main PSK. <img src="/images/graemlins/smile.gif" alt="" />

My 2 cents...