Nowadays, I pack a DMT Fine Mini-Sharpener. It seems to ldo the trick for touching up a blade and costs about $12.

This is one of the sharpening options Doug mentions on his Keeping Sharps Sharp page.
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Victory awaits him who has everything in order — luck, people call it. Defeat is certain for him who has neglected to take the necessary precautions in time; this is called bad luck. Roald Amundsen