ADDED   src/0dev.org/commands/mtf/main.go
Index: src/0dev.org/commands/mtf/main.go
==================================================================
--- /dev/null
+++ src/0dev.org/commands/mtf/main.go
@@ -0,0 +1,64 @@
+package main
+
+import (
+	iou "0dev.org/ioutil"
+	mtf "0dev.org/mtf"
+	"fmt"
+	"io"
+	"os"
+)
+
+func main() {
+	var code int
+	switch {
+	case len(os.Args) == 1:
+		code = transform(os.Stdout, os.Stdin)
+	case len(os.Args) == 2 && os.Args[1] == "-d":
+		code = reverse(os.Stdout, os.Stdin)
+	default:
+		fmt.Fprintln(os.Stdout, "Usage: mtf [-d]")
+	}
+	os.Exit(code)
+}
+
+// Transforms the data according to the move-to-front algorithm
+// I/O is buffered for better performance
+func transform(output io.Writer, input io.Reader) int {
+	var (
+		err     error
+		buffer  io.Writer = iou.SizedWriter(output, 4096)
+		encoder io.Writer = mtf.Encoder(buffer)
+	)
+
+	_, err = io.Copy(encoder, input)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, "Error while encoding.\n", err)
+		return 1
+	}
+
+	// Flush the buffer
+	_, err = buffer.Write(nil)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, "Error while flushing output buffer.\n", err)
+		return 1
+	}
+
+	return 0
+}
+
+// Reverses MTF`ed data and writes back the original bytes
+// I/O is buffered for better performance
+func reverse(output io.Writer, input io.Reader) int {
+	var (
+		err     error
+		decoder io.Reader = mtf.Decoder(iou.SizedReader(input, 4096))
+	)
+
+	_, err = io.Copy(output, decoder)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, "Error while decoding.\n", err)
+		return 1
+	}
+
+	return 0
+}