The place where we can chat about Ars Magica subjects--though if it's a big enough comment or question you can always open it's own topic. This Table Talk is generally lighter, briefer discussions of metagame and other game issues.
For example:
Poring through the library over at the Mystikae Eikona wiki http://mystikae.wetpaint.com/page/The+Library I find what may be may favorite book title in all the Ars Magica literature I have read over the years:
Tractatus: “Bonisagean Effulgence in Greek Mysticism”
Granted, I came up with it myself, but it's still a great title! Sounds like an article in St. Vladimir's Seminary Quarterly, someone's ordination thesis... 8)