So here's mine.
Primary view:
It's a Forge Steel toolbox. The main section is all the kingdom cards (not arranged by expansion, though they used to be), to the right are the events and mats etc.
Individual card dividers are BCW card dividers labelled (oh the timesink) with printed-off scans of the labels from the boxes stuck to them.
Separating each column (and lending strength in general) are a grid of interlocking plastic strips, hard to describe and I confess I have no idea where they came from, they were discovered by my wonderful mother:
Closed views:
Below the main section, bottom left and bottom right (either side of the handle) are all the non-kingdom cards, Spoils, Ruins, Base. For Provinces you take out the whole bottom left thing (string to lift them all out at once) to get all the relevant base cards and for Colony games you take out the whole bottom right (extra set of Estates/Duchies/Provinces there). You have to pick and choose a bit if you need Potions and Ruins and Colonies or something.
Empires should fit, there's more space remaining in the main section than there looks, but I may also have to take one set of base cards out of one of the sections (who needs two distinct sets!) and use that space for new kingdom cards. Many more cards after Empires, I'm screwed!
The brown thing is a pouch for all the tokens that straps to the handle:
Overall it works pretty well, I'm pretty proud of the construction (hence the showing off), but I'll be sad when inevitably the expansions overflow it! There are bigger variants of the Forge Steel toolbox, but it's heavy enough now that I've torn between making it bigger and just starting a new box. Or maybe I should just stop buying expansions.
Anyway, there you are.