It's a bag held closed with a separating zipper, which when unzipped looks like this:
There are partitions sewn inside that can either be fastened via velcro to the sides for an open compartment or, as below, divided into smaller sections using that same velcro to hold the partitions.
The tote can be used for ever-so-many types of things, and the side flaps can be held down and out of the way with the invisible (or regular) magnetic snaps. There are pockets on both ends of the tote, too.
It can be zipped up with items inside, keeping them secure.
There are also two other strap options, which you can see on LiEr's blog post (plus there's a supplies list in case you know you're going to buy the pattern and want to get a jump on getting ready while you wait for it). I chose to make the straps that have the rectangular rings, because 1) that's the one LiEr asked me to make, and 2) that's the one I would've chosen, anyway, because the straps fold down and out of the way so nicely (plus hardware is cool).
The pattern has been going through a lot of revision, so by the time it's all said and done, it'll hopefully be 'just right'. It's not a pattern for beginners, but if you have some bag-making experience, you should be able to handle it. There are some curves to sew, including the zipper installation, and there are some thick seams than can be challenging, so keep that in mind.
LiEr also posted a tutorial for making little collapsible inserts that are just the right size to fit inside the Port & Sort Tote. You can find that tutorial here. I wanted to try one for myself, and you may have noticed it in the one photo above. Here's a better look:
The outer fabric for the tote and the insert are from Jess's In Theory barkcloth collection for Cloud9 Fabrics.
Below is a little collage showing the insert, which has a zippered bottom that when unzipped allows the box to be folded flat, or even into quarters to maybe fit in your pocket! I love it!
As I said, I've got the pattern now for a final proofread, so I'd best get at it! I'll post again when the pattern is available to buy. SOON! (Relatively speaking, that is. ;) )