Make a command block redstone clock using /setblock ~ ~1 ~ redstone_block 0 destroy, put a sticky piston on the side of the redstone block facing the redstone block, turn on and off the piston in one tick (so that the redstone block is not touching the command block) and turn on the piston again. This creates a redstone block that is real (can mine using a pickaxe in survival and drop the item).

Video:
http://youtu.be/HKtvUITZbTc

P.S. this is my first bug report and I'm not that good with English please ask me if you have any questions regarding to this glitch.