porous => porosity generous => generosity
hackers happily generalize:
mysterious => mysteriosity ferrous => ferrosity obvious => obviosity dubious => dubiosity
Also, note that all nouns can be verbed. E.g.: "All nouns can be verbed", "I'll mouse it up", "Hang on while I clipboard it over", "I'm grepping the files". English as a whole is already heading in this direction (towards pure-positional grammar like Chinese); hackers are simply a bit ahead of the curve.
However, note that hackers avoid the unimaginative verb-making techniques characteristic of marketroids, bean-counters, and the Pentagon; a hacker would never, for example, `productize', `prioritize', or `securitize' things. Hackers have a strong aversion to bureaucratic bafflegab and regard those who use it with contempt.
Similarly, all verbs can be nouned. This is only a slight overgeneralization in modern English; in hackish, however, it is good form to mark them in some standard nonstandard way. Thus:
win => winnitude, winnage disgust => disgustitude hack => hackification
Further, note the prevalence of certain kinds of nonstandard plural forms. Some of these go back quite a ways; the TMRC Dictionary noted that the defined plural of `caboose' is `cabeese', and includes an entry which implies that the plural of `mouse' is {meeces}. On a similarly Anglo-Saxon note, almost anything ending in `x' may form plurals in `-xen' (see {VAXen} and {boxen} in the main text). Even words ending in phonetic /k/ alone are sometimes treated this way; e.g., `soxen' for a bunch of socks. Other funny plurals are `frobbotzim' for the plural of `frobbozz' (see {frobnitz}) and `Unices' and `Twenices' (rather than `Unixes' and `Twenexes'; see {UNIX}, {TWENEX} in main text). But note that `Unixen' and `Twenexen' are never used; it has been suggested that this is because `-ix' and `-ex' are Latin singular endings that attract a Latinate plural. Finally, it has been suggested to general approval that the plural of `mongoose' ought to be `polygoose'.
The pattern here, as with other hackish grammatical quirks, is generalization of an inflectional rule that in English is either an import or a fossil (such as the Hebrew plural ending `-im', or the Anglo-Saxon plural suffix `-en') to cases where it isn't normally considered to apply.
This is not `poor grammar', as hackers are generally quite well aware of what they are doing when they distort the language. It is grammatical creativity, a form of playfulness. It is done not to impress but to amuse, and never at the expense of clarity.