What you need (Works in survival and Creative!)
1 Sticky Piston (facing any direction but up and down)
1 Slime Block (place this on the sticky pistons head)
1 Stone Block (place this on the slime block following the piston head)
1 Redstone Block (place this on top of the slime block
(Sticky Piston on the right, Slime block in the middle, Default Block on the left and a Redstone block on top)

Example:
P = Piston, S = SlimeBlock, D = DefaultBlock, R = RedstoneBlock

    [R]
[D][S][P]

keep in mind this model, was discovered by me, although I don't know if I'm the first to discover this model if I'm not comment on this "blog" and tell me who made it.

What is a Block Updater
A Block Update Detector or BUD, is a simple redstone device that can be used to detect if a block has been updated, for example when a dirt block has grass grow on it or when a block is broken. To activate the BUD you must place the objective block next to the open sides of the piston and then update the block.