For me, the Star Wars movies really set the tone for what I want a Star Wars campaign to be like. And in the original trilogy, one of the main elements in the Saga was the Millennium Falcon. From her first introduction on Tatooine ("What a piece of junk!") to her trials and tribulations on Hoth and Bespin ("Would it help if I got out and pushed?""It might!") to her ultimate triumph at Endor ("Yeeehooo!") the Falcon was every bit as much a 'supporting character' as the droids and 'NPCs' surrounding the heroes. So when I started my campaign, I really wanted there to be a central 'ship' for the party.
In the case of the Vermillion crew, that central party ship was (initially at least) the "Lightblade", an ex-smuggling ship owned by Marko Razmussen (an ex-smuggler). It was a YT-1300, just like the Falcon. In fact, it was pretty much identical to the Falcon (except in it's initial stats). But so what if it wasn't terribly original, it was a great base of operations and saw the group through many of it's early adventures. What I quickly discovered, however, is that many of the adventure modules had scenes in which the party ship is either captured or crashed or (in come cases) outright destroyed. That just irked me. Still does. It also made me have to modify quite a few adventures to give the Lightblade a fighting chance to survive rather than have it meet yet another 'scripted' demise.
Later in the campaign, as the players got more money (and began to branch out a little, mission-wise), another ship came into the fold. Again, it was a YT-1300, but this one with the cockpit on the port-side (again, I know, real original, so sue me). This, however, was the 'Stormbringer'—a freighter that gave up all pretenses at being 'legal'. It was a gunship, pure and simple, and was also outfitted for bounty hunting (which makes sense considering it's captain, Oman, took up the trade for a time). The group would vary which ship they used based upon what mission they were going on—Lightblade if they were trying to pretend legitimacy or the Stormbringer if they were going 'fangs out'.
A third ship entered the family much later on, but really played no major part in the adventures. This was a luxury yacht called the "Starlight Express" (as I recall), purchased jointly by Oman and Harold Hugganut. And strangely enough, it was just that—a luxury ship, with little emphasis placed on combat capability. Kind of an oddity for my group, but an interesting one. The ship was of a deign stolen from another game book (Worlds Beyond), so it wasn't part of official 'canon'. I guess that makes it one of the more 'original' ships in my games.
Other notable ships that have appeared in my campaigns at various times are:
The "Trivial Pursuit". This was a big Barloz freighter owned by Adren. Over the years of playing, this one took as much of a beating as its owner—at one point being nearly destroyed. It was rebuilt, however, with the engines from a Guardian-Class customs cruiser—making it a very FAST flying brick.
The "Lame Duck". This was only BRIEFLY used in one of my short-lived side campaigns. One of my friends (Eric Meldstadt) drew it during my first year at college and I was so intrigued I just had to make up stats. It was this oblong, asymmetrical monstrosity of a ship—and I love it still to this very day.
The "Handree". This was a Corellian Gunship—in fact the ship featured in the adventure module The Isis Coordinates. It was rescued by the PCs in this adventure, and was later commanded by Arianne during the Battle of Endor. Unfortunately, the bathroom humor my group (and myself) was so fond of soon gave this ship the unfortunate nickname of the "Handjob". Ahem. Yes. Moving on.
The "Taking Care of Business". This one I had forgotten about entirely (Thanks Steve2 for reminding me). When Todd retired his Wookiee character, Ruukhan, he started a freight-hauling business and this was his personal ship. I believe it was a Ghtroc-class ship. And once again, the 'humor' thing came into play—the TCOB was soon known as the TCBY.
But anyway, this thinly veiled excuse for me to reminisce about our party ships did have kind of a point—and that is this: Ships in the Star Wars universe should not be any more 'disposable' than any other character. By keeping (and developing) a single (or couple) ship(s) you can develop a lot of 'character' with them—give the group a bit more depth and attachment. And if/when the ship is ever destroyed (or severely damaged), there will be some level of emotional attachment to it—it becomes dramatic rather than just "Oh well. I'll get a new one."