Alias & the purpose of Rambaldi
This one goes out to all yall, my awesome Googlers/Yahooers, and for the record, I did misspell it as "Rimbaldi" -- embarrassment!
Just what's the point of having Rambaldi come in and out of Alias's story lines, all willy-nilly like? It's very simple: because it's convenient.
One of the more common tags associated with Rambaldi is that it's reminiscent of X-Files -- and with all the doomsday/occult prophesying and tentacles of conspiratorial cabals (the last being this season's most significant development, Rambaldi-wise), there is validity in that claim. With Rambaldi and all the attendant plot arcs that spring from it, JJ Abrams is able to satisfy a lot of his pop culture appetites (of course, which is on top of the melodrama and high tech espionage) in addition to appeal to other fans of such genres.
More to the point, I suspect, Rambaldi is a vehicle for having, first of all, a mythology arc (and in this case, I don't mean mythology like Greek -- more like the overarching/fundamental thread of story that runs throughout the entire series (again, cf. X-Files)), which is a way of satisfying the long-time fans.
However, in a bid not to alienate new viewers, Abrams also avoids developing the Rambaldi arc in a traditionally linear way, i.e. with a concrete and final conclusion. We thought that Rambaldi had been dispensed with in the season three premier, "The Two," when Sloane reported that the culmination of all of his Rambaldi collecting resulted in a single word: "Peace." Lo and behold, we've got a second "end-game" in progress with the introduction of the Passenger. Now, the newbies can go through the same stunning twists and turns that the veterans have witnessed. ("stunning")
It's a circular plot arc that can be massaged into the show at will for the seasons where JJ wants to emphasize the action-adventure side of the show (as opposed to the melodrama-laden second season (and if this three season sequence is any indication, we'll get heavy with the sighs again next year)). But even more importantly, it's an excuse to put Syd into different situations that call for outrageous costumes and cleavage.
But to return to my point, and this is where I'm going to get metaphysical, so bear with: circularity, oddly enough resonates with Western thematic concerns -- the constant gazing back into the past (think: the general fascination with the Quattrocento and Nostradamus; think: the yearning for Eden; think: nostalgia for one's childhood/the "Good Old Days"; think: the desire to return to the womb) coupled with the future/ultramodern aesthetic (When is this season set? Why, two years from now!), which in turn ties into notions of fate, i.e. a manuscript written six hundred years ago is outlining the actions-yet-to-be-taken by Sydney et al. The worry of Rambaldi prophecy coming true would be the equivalent of laying waste to Western perception of time -- the past is written down, but if the future is written down (and written down in the past no less!), how is the future different from the past? Is the path of the entire universe already pre-determined? (And forget not the free will issues that crop up now.)
Rambaldi collapses time into a circle. What we thought was the end, is just another beginning.
(And who the hell wants to go back to the days when Will was Tooly McTool and Syd still held a warm place in her heart for Noah??)
Seriously, it's a potent worry for those trained in the Western schools of thought. Our notion of history is predicated on progress, and to have a 15th century crazy map out our lives (and also invent gadgets that rival modern-day technology) undermines our march towards that civil paradise (Eden again! See? The past haunts us! Of course, "progress" entails a current state as being better than before -- defining the present in terms of the past. The past is inescapable, to those who remember it or not.).