I went through this problem for a while, the same with salad cream and toilet paper :)

Could also be useful to add:

* an attribute that indicates how much of a thing has been used

* an item's age or purchase date

* the expiry date or best before date (yes, yes...I know these things aren't precise, and I decide if something is still good on the basis of does it look ok? does it smell ok? and common sense when it comes to fish/meat)

For example...when I occasionally make hummus, my part-used jar of tahini paste ends up at the back of the cupboard where it gets forgotten about but is still within its use-by date.

On the next trip to the supermarket, where I include ingredients to make hummus, I end up buying another jar of tahini paste because a) I can't remember if I still have tahini paste and b) if I do remember about that jar, was it opened? how much is left? and is it still good?

Knowing the state of perishables, whether unopened or part used would help save on waste and save money on unnecessary purchases.

Also I think a better name would be "Personal Stock Control", "Storage System" makes me think of disks and data storage.

Just a thought or two.