Great Deletion
From Elite Wiki
One of two great losses of early Oolite history. The BB website lost many thread 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 consigned to oblivion.
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: http://aegidian.org/bb/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 more accurately, their ReadMe's being lost):
See the historical section in Oolite.