My solution to http://tour.golang.org/#47

fib.go

package main

import "fmt"

// fibonacci is a function that returns
// a function that returns an int.

func fibonacci() func() int {
	a := 0
	b := 1
	f := func() int{
	  a,b = b, a+b
	  return a
	}
	return f
}

func main() {
	f := fibonacci()
	for i := 0; i < 10; i++ {
		fmt.Println(f())
	}
}

Thanks to mhilton