Verus amicus amore more ore re cognoscitur.
This has been percolating through the Latinteach mailing list. It means, "A true friend is known by his love, his habits, his speech, and his deeds." But no one knows where it came from. If you google it, you will find a surprising number of people quoting it and attributing it to Virgil. It's nowhere in Virgil, though.