After reading the travel and carry-on food comments, my honest and scientifically supported comment may have offended nut-allergy people (sorry!), so I'll make up for it by promoting (?) a peanut-free product. I have a sample packet at home that bf got at an allergy & immunology meeting but haven't had a chance to try it yet. maybe I'll keep it until my trip, which is soon.
Do you like sunflower seed butter (the major brand seems to be Sunbutter)? does it taste like nut butter? are they readily available and cheap?