Site is back up again, obviously.
Congestion 384 This is, I think, what Congestion 1024 could have been. The idea is the same, make maps whose area accessible to the player is restricted to a given size, in this case a 384x384 square.*
A 384 square is a lot smaller than a 1024 square. It is impossible to miniaturise an entire "normal-sized" map into this size - there simply isn't the room to do anything other than one room with a few monsters in. So 1024's problem of masses of filigree detail and cramped, annoying gameplay is avoided. It's just a set of 20 tiny maps that can all be played in under a minute.
I really like this wad and recommend it.
* following 1024 and 64, some might point out 384 is not a power of two. However perhaps the pattern is not powers of two, but numbers that end in 4! The most important thing is to be a multiple of the flat size (64) or perhaps the common texture widths (64, 128) for ease of alignment. Right?