Traction by Traction Software  is a great project log tool. Udell has
reviewed it . The original design for the tool was as a true project log.
Log entries could be added via email or the web (with attachments). Log
entries could be categorized on a paragraph by paragraph basis. Searches on
a category only showed the relevant paragraph from the whole entry.
Categorizations might be about content ("competion", "jabber"), or process
("bug:27","milestone"), or importance ("news"). The project log could then
be displayed by content, ordered by date, and formatted according to
importance. Current versions have very good integration with Microsoft
US Engineering Team Leader