So, I really want to suggest that we incoroprate P52 - the oldest extant fragment of the New Testament we have:
It would convey the "People of the Book" and the scholarly thing we're going for.
So, how would I suggest it?
So, I'm a huge fan of the mosaics in Ravenna (Italy), because they really are associated with Patristic Christianity in my mind. They are the classical art form of the fledgling Christian community, and a mosiac feel for our header would cause me great joy...
Mosaics also have the added advantage of making what I believe to be the perfect theological point this site is trying to make. The church may be massively fragmented - but take just one step back, and it is a beautiful thing. Individually, every piece plays its part - even the cracks and fissures that divide - into weaving the tapestry that is God's plan. God uses the broken pieces of his church and our lives to make a masterpiece - which is exactly what a mosaic is.
This is my current favorite symbol to represent Christianity:
The Chi Rho is one of the earliest forms of christogram, and is used by Christians. It is formed by superimposing the first two (capital) letters chi and rho (ΧΡ) of the Greek word "ΧΡΙΣΤΟΣ" =Christ in such a way to produce the monogram. Although not technically a Christian cross, the Chi-Rho invokes the crucifixion of Jesus, as well as symbolizing his status as the Christ.
It also contains an even earlier symbol from "I am the Alpha and the Omega, the first and the last, the beginning and the end." (Revelation 22:13 ESV) It is also a common symbol found in both the Greek and Latin traditions.
I also like the circle around the whole thing. I'm not sure if it's a particularly Christian thing, but I like that it looks like a wheel.
If we are going to use standard Christian symbols, we should probably have as much going on as possible to represent the mosaic of people and traditions our site represents.