here

I think, therefore I shall eat pizza.

I'm not sure about subtleties in the grammar. I think pizza should be declined as pizzam, but that would make it harder for non-Latin readers to get the point.

Here.

Clearly derived from "Ceterum censeo Carthaginem esse delendam" which gets its own Wikipedia page.

This raises the question - how should Facebook be declined? My answer - just don't sign up for it.

Here.

By web search: "Whatever it is, I fear the girls, even when they kiss."

I can't find a source, but presumably a reference to
Vergil, Aeinid II.49
QUIDQUID ID EST, TIMEO DANAOS ET DONA FERENTES.
Whatever it is, I fear the Greeks, even bearing gifts.

vos nescitis quicquam, nec cogitatis quia expedit nobis ut unus moriatur homo pro populo et non tota gens pereat here.

Biblical, "You do not realize that it is better for you that one man die for the people than that the whole nation perish." John 11:50 (spoken by an antagonist.)

here.

It seems fractured, but I think
My Latin sig is criminal because I think stupid people are sane and clever.

here
Quote from Horace, the full version of more common "carpe diem".
Seize the day, trusting as little as possible in the next

http://linux.slashdot.org/comments.pl?sid=564539&cid=23554467

My hovercraft is full of eels (again).

Here.

Translation by Google:
"The more corrupt the state is then the more numerous the laws." -- Tacitus, The Annals of Imperial Rome.

This may be a Libertarian/Conservative catch-phrase.

Here

Thus the biscuit crumbles.

Navicula hydraulica plena anguilarum est. Omnes castelli tuus nostri sunt. Ed elli avea del cul fatto trombetta.

"Navicula hydraulica plena anguilarum est" = "the hovercraft is full of eels".
"Omnes castelli tuus nostri sunt" = "all your base are belong to us".
"Ed elli avea del cul fatto trombetta" = ?
"Words" doesn't recognize enough of this that I suspect it is not Latin.
Confirmed by websearch: It is Dante making a fart joke.

here.
See "Sed quis debugget ipsos debugator?" a few entries ago. (Which is correct?)

here
Minutus cantorum, minutus balorum, minutus carborata descendum pantorum

Translation found by google:
"A little song, a little dance, a little seltzer down your pants."

here.

The first phrase is famous and googlable.
"Thus passes the glory of the world; not with applause, but with bad Latin."

Presumably "Who will debug the debugger?"

Orationem pulchram non habens, scribo ista linea in lingua Latina

And translation via Google:
"Lacking anything witty to say, instead I offer this tagline in Latin"