Before the speculation, the facts.
Our introduction and understanding of the Arrow Station came primarily through the eyes of the tail-end section survivors who holed up there to seek refuge from The Others. Goodwin said, "It looks like some sort of storage facility." However, Goodwin was a no-good, duplicitous Other at this time, which makes me think cynical about his input. The inside was relatively bare though, with the only (so far) notable find being a large box that contained: a Bible, a glass eye and a radio.
There's popular belief that the glass eye belonged to Mikhail. Just because the socket beneath Mikhail's eyepatch was revealed as healed over during Through The Looking Glass doesn't mean the glass eye couldn't have been his, but to suggest anything further would be pure conjecture (and not my concern here).
The Bible contained a piece of missing footage from the Swan Orientation film. The missing piece showed Marvin Candle warning that use of the computer in The Swan for communication purposes was strictly prohibited. (Aside: Arguably the reason this piece of film was taken was to encourage later occupants to use the computer for communication. Aside over.) Interestingly, the Bible was most likely brought to The Arrow by Radzinsky. The same Radzinsky that worked on the Blast Door Map. On the Blast Door Map, Radzinsky had made the following notation about The Arrow. 'I think we're on the same wavelength.'
If we take the statement - 'I think we're on the same wavelength' - and run with the idea that Radzinsky was aware of parallels between the Arrow Station and the Swan Station we may potentially be leading down a promising path. Let's look for clues. Firstly, the name. Arrow. This suggests direction, or pointing to something. I'm not so sure I would go with the blatantly obvious idea (that the Station is situated at a point on the Island where it literally points at something else!) which leads me to believe the Station itself is meant to point the way, to give direction. I presume that means it will offer direction due to the nature of the studies taking place.
Which begs the question: What was Dharma studying there?
Before the what, let me tell you who. Horace Goodspeed. When Horace met Ben and his father arriving on the Island he was wearing a Dharma jumpsuit with the Arrow logo upon it. He was wearing this same item of clothing on the day he died; this suggests that for many years Horace spent his time working in the Arrow. Clearly The Arrow is a more significant Station than the sparse rooms and bare furnishings the tail-section survivors found suggests.
Horace's field of study within the Dharma Initiative was mathematics. Naturally, this brings up the good old Valenzetti equation. Potentially, Horace's character may be the means by which this concept is introduced to the show. Perhaps Horace spent his time on the Island studying the 4 8 15 16 23 42 equation in The Arrow. 'I think we're on the same wavelength,' stated the notation from the Swan to the Arrow. The Swan Station that has 4 8 15 16 23 42 etched into its hatch. The Swan Station that requires 4 8 15 16 23 42 required as a code entered into a computer. If The Arrow is on the same "wavelength", and Horace worked at The Arrow, and Horace was a mathematician, those 4 8 15 16 23 42 numbers loom pretty large. . .
Ordinarily I wouldn't feel particularly compelled to push this point, but since Horace Goodspeed worked at The Arrow I am forced to consider its importance. To be frank, The Arrow station revealed so far is a bit of a dump; stone walls, scarce furnishings - not the kind of place serious scientific study was taking place. And so maybe there's a hidden room, like what was revealed with The Staff Station during the episode D.O.C. Or maybe, like The Flame, there's an area underneath the Arrow Station that contains juicier treasures. Maybe, just maybe, there's another computer in there. I think we're on the same wavelength. That phrase just keeps coming back to me.
There's every reason to believe The Arrow Station is going to be a Dharma facility we get to know a whole lot more about in forthcoming episodes. Horace Goodspeed is certain to be a character that features again, and since his principle work belonged to The Arrow it's hard to imagine how further information about this Station cannot accompany further information about Horace, or vice versa. Furthermore, we've got that glass eye mystery to concern ourselves with. So while, at the close of season 3, The Arrow appears to have been relegated to the status of least interesting Dharma Station, I believe it withholds the capacity to be the most fascinating. I trust you're on the same wavelength. . .