Traveling Shiva (Natarajasana)
This one may get some onlookers, but it is such a great one to slip in while traveling. Sitting for long periods of time really tightens up the front of the legs (quadriceps, hip flexors, iliopsoas muscle), as well as the upper back. Dancing Shiva counters this by stretching the fronts of your thighs, and opening the heart.
TO DO: Standing in mountain pose with both feet parallel, bend the right leg and reach back with the right hand to hold the right ankle. Draw the foot towards the buttocks, and start to feel the opening through the front of your right thigh. This may be enough, or you can hinge forward slightly and begin to stretch the leg back behind you. You can do this freestanding, or use a wall or your traveling companion for balance. Release and try the second side.