This mod was created using MCreator http://mcreator.pylo.si
The Daytiminator is a wand that sets the time to 0 when you right click while holding it (has 50 uses).
Eeeh. Too expensive, I'd say. You could just use a bed...
It's gonna take you the same inventory slot except that the bed has unlimited uses.
Yeah, I just thought it would be useful for creative if you don't want to type in the command to make it daytime
Eh? You can easily hook up a daytime detector to a NOT-gate (aka redstone torch) and a command block to automatically reset the time. I use that, but with weather.
The trick is to use a structure so the block's at lower light than the exterior, so as soon as there's a change, it stops working, the NOT gate turns from off to on and the command block is executed.