[Snapshot14w25a]Sign

/setblock ~0 ~1 ~0 minecraft:standing_sign 0 replace {Text2:"{text:\"Cmd\",clickEvent:{action:run_command,value:\"/give @p minecraft:command_block 1 0\"}}"}

/setblock ~0 ~1 ~0 minecraft:standing_sign 0 replace {
	Text2:"{
		text:\"Cmd\",
		clickEvent:{
			action:run_command,
			value:\"/give @p minecraft:command_block 1 0\"
		}
	}"
}