I just spent some time with a a BOM, a Mouser shopping cart, and my parts bins. Managed to shave off 25+ € from the cart by just cross-checking what I've got already.
A real pity that the only FOSS software that does parts inventory, PartKeepr, is a festering PHP infection. I could use the functionality.
I HAVE been pondering an "I can do that" attempt, in my preferred perfidity, Perl + Postgres, (FAPP, as it's known*) but that would take a serious supply of round tuits and some intense boredom to want to escape. But it would Feel Right. So 2001. Before the PHP shitstorm and before the JavaScript avalanche. (of course, one does take advantage of CSS to build the UI, because CSS is not a piece of crap; it's actually reasonably clever. )
* FreeBSD, Apache, Perl, Postgres