I've started to think in terms of "cards" which are fairly similar.
Obviously CardiganBay decided to take the idea of cards so seriously, it's even in the name. :-)
I think I first saw the term "card" used in WAGN (which is now Decko)
But what really sold me on this finer-than-page granularity was the SmallestFederatedWiki. Even though I finally disliked them for editing (LeavingTheSFW) many things about them did make sense to me. Hence Cardigan Bay.
People often talk about "index cards" as the physical paper equivalent. Even though these are largely not "indexes" (Except my stuff actually is a lot of LocalIndexes ;-)
DynamicLand seems to use "card-like" things too.
TiddlyWiki has "tiddlers" which I guess are the same.
See also :