For my knives, I use one of these sharpeners which does a decent job for my needs. Also the sharpener is small enough (2-5/8" wide x 2-1/2" tall) to fit into almost any kit. These sharpeners retail for around $7.00 but are often on sale locally for about 1/2 that price.

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Earth and sky, woods and fields, lakes and rivers, the mountain and the sea, are excellent schoolmasters, and teach some of us more than we can ever learn from books.

John Lubbock