Great Deletion
One of two great losses of early Oolite history. The BB website lost many threads due to the settings (automatic thread deletion if no activity for 6 months) back before August 2008. Many of Aegidian's & Ahruman's posts were thus consigned to oblivion (they had roughly 2,500 each in Oct 2007).
See: We are losing our collective memory (Aug 2008)
For an example of what was lost: Giles' excellent and thorough guide to making your own dock: https://bb.oolite.space/viewtopic.php?p=20007&highlight=subentities#20007
The other loss was due to Oosat2 going down and the old oxp's on it being lost (or as it eventually worked out, their ReadMe's being lost).
See the historical section in Oolite: Littlebear saved the day with his private collection, but his copies of the OXPs lacked the ReadMes.
But comments were also postable on Oosat2 about the various OXPs on it (see Roberto's 2006 comment here) - so these too have all been lost!