You can make protein "pudding" w/ some protein mix (I do 1 scoop of regular ATW protein + 1 scoop of casein protein - the casein protein mixes up thicker and requires more water - feels like you're eating more) + 1-2 tbls PB + 1 Splenda packet and then mix in enough water (I use cold coffee) to make a "mush".
You can also add in stuff like ground flax meal, ground up almonds or peanuts, you could probably throw in some heavy cream, etc.
And its compact & travels well (Note - but the airlines consider it a "liquid" so if its > 3 oz, you can't take it onboard w/ you.)
Another thing you can do is make protein pancakes - these also travel well:
* make 1/2 -1 c of oatmeal who you normally do (for me- fill w/ enough water to cover the oats, nuke for 90 sec)
* mix in 1-2 scoops protein mix (I stick w/ vanilla - not big into weird flavored oats)
* mix in 2 Splenda packets - or to your taste
* mix in 2 egg white + 1 whole egg to get a cake-batter consistency (sometimes have to mix a lot to get the egg mixed in w/ the oats)
* spray PAM into a large fry pan, pour your batter into the pan and cook it like a giant pancake (or make smaller blobs of the protein batter for smaller pancakes)
They're good w/ jelly on 'em!