The phrase "fuck your brains out" is kind of intriguing in the context of the theme of the libidinal economy. Compare "fuck the shit out of me." Also compare Lyotard maybe:
"Now, here comes the question of symbolic exchange: this fear [of impotence, of things going nowhere, of nothing happening] is not, as we have thought, the fear of no longer being able to give. The category of the gift is a theatrical idea, it belongs to semiology, it presupposes a subject, a limit of his proper body and his property, and the generous transgression of this property. When Lacan says: to love is to give what one has not, he means: to forget that one is castrated. It should mean: one never has anything, there is no subject, and so there is nothing but love; not only is there never anything to give because one has nothing, but there is no-one to give, or to receive. It is in the theory of signs that donatory exchange (or the gift as the primitive form of exchange) may be represented as the attribution of devolution of an object charged with affects to someone who at the beginning of the cycle didn't have it: for the sign is just something which replaces something else, hides and manifests something else, for someone, for the addressee (and also for the sender). This problematic, coming from Jakobson to Lacan, that is to say the theory of communication, carries with it the entire philosophy of the subject, the philosophy of a body haunted by self-appropriation and property since the theory of communication is obviously just as much a piece of economic theory. Mauss must not be read as the discovery of a 'precapitalist', or at least a mercantilist, economy, but as the invention and the perfecting, in the heart of this economy, of its indespensable complement of anteriority-exteriority. Replace the gift with symbolic exchange and you remain in the same sphere, for exchange also takes place amongst unitary bodies or those destined to be unitary, even if they are prevented for ever (by the 'bar of the signifier') from bringing this unity about, and even if they are always driven by their splitting in two, by the Entzweiung, as Hegel used to say, to exchange something, even if only pieces of themselves; the exchangists remain perforated, like poles or ideas of (mercantilist) reason rather than as existants, it remains that exchange requires this polarization, this encephalization, and an in-and-out movement, a cycle of flows, the circle of a market and its central balance. Whether or not one exchanges affects does not modify this configuration, it simply dramatizes it. [...] Exchange is no less 'humanist' than production [...] Circulation is no less suspect than production, it is only, as Marx well knew, a particular case of production taken it the broad sense. Let's rather place oursilves in the sense of this production in the broad sense, which is the general metamorphosis of everything which takes place on bodies and inscribes itself into the social body, haunted by the idea of a ceaseless general metamorphosis, or of a general production without inscription, which is nothing other than the great skin; we wonder instead what are the characteristics of the figure which makes the passage from this latter to inscribed production, the characteristics of the dispostif of inscription which constitutes social voluminosity."He goes on to talk about a urinal.