DIY box shelves

As some of you may know, we have a spare bedroom in our house. So far, it's just been used as a place to store toys, which means they end up all over the floor and rather disorganized, regardless of our efforts to keep them in boxes. So, we decided a little while ago to attempt to make some shelves to store the boxes so that everything could be kept off the floor at least (and so guests have some space in there!). We earn rewards points on our credit card which can be redeemed for Bunnings vouchers, so we headed off there on the 9th May to buy some MDF and screws and so on.
4 weeks later, this is the result. It didn't take nearly as long as I thought it might have! Having a router to do the joints meant that the structure was reasonably easy to do and quite strong - there's no bracing of any sort.
The slowest part was actually the painting - cold weather recently has made it hard to do. But it's now done. And overflowing already...