i tried it too, with one small bottle and a larger one, and i pushed them onto bamboo poles instead of nailing the tops to a board. as corwen says, they're not pretty, but could look all right for kids if you paint them. i've got mine in an inconspicuous place. they whistle along merrily when the wind's at all westerly, which it usually is. to me it sounds like a conversation, words spoken too low for the words to be made out, and it's strangely soothing, as if it gives the breeze vocal chords and the wind is pleased.