I stumbled upon this (http://www.brewmasterswarehouse.com/brew-builder) on homebrewtalk, its an online recipe/ordering service, it's a really cool idea but I imagine a pain to actually implement.
I've often thought it would be good if someone made something similar like this website (http://www.supercook.com/#/recipes/All%2520recipes/), where you enter all the ingredients you have and it gives
you a rough idea of the beers you could brew with what you have, at the moment I use a spreadsheet to keep an eye on all the ingredients I have
and relevant dates. If anyone with some experience in that area would like to do that feel free to take my idea develop it and give me a commission.
Beersmith has an inventory section, handier than maintaining a spreadsheet. You can remove all the items once a recipe is made.
An add on for that which offered you recipes based on whats in your inventory would be great.