Dungeons of Dredmor: Conquest of the Wizardlands DLC Blog Post

In case you're interested in reading more on the recently announced Conquest of the Wizardlands DLC for Dungeons of Dredmor then you might want to check this blog post from the developers on it. Luckily, they also delve into the design reasons behind their additions:
Inventory has been a problem in Dredmor forever. This is of course a game based around finding piles upon piles of silly objects in the grand tradition of looting that made games like Diablo strangely compelling. We need the multitude of items for the sake of the act of looting as well as to be a vehicle for delivering so much of the humor and backstory such as it is of the Dredmor universe. In short, Dredmor wouldn't be Dredmor without all the useless crap lying around.

Players, however, tend to be driven rather mad by the highly limited space in their inventory, and quickly, as it can be filled up within the first dungeon level. People write us letters about just how awful this is, trust me, and we read them.

Yes, we could just make the inventory infinitely large. But this creates a few problems: of UI implementation (which can be fairly simple, if potentially tedious to use), and of gameplay balance (which is not so simple). Apart from skills & spells, items are the solutions to problems met in the course of gameplay, so allowing the player to hold every single item in the game means they can solve any problem in the game by shuffling about in their bag and pulling out the magic wizzawoozle. Worse yet, this makes every game of Dredmor rather similar by allowing the player every option at the same time rather than forcing them to make choices about what they will take with them and what they will leave. Take the wizard hat OR the knightly helm, not both.

Ideally the player has to make hard decisions about the set of solutions they will have on-hand to deal with the dungeon. See for example our 7-skill system that both limits and enables gameplay ( far more elegantly than our limited inventory system, I must concede).

So: The Pocket Dimension gives you an effectively infinite inventory with the gameplay-relevant friction of a 32 or so turn cooldown on using the portal key.