Last week Sam in the UK posted to the UDXF newsgroup information on a mystery HF ALE net known as the "055 Net" due to the station ALE Address seen sounding on the net.
Frequencies monitored 2007 (ALE/USB)
5782.0 9070.0 10618.0 10627.0 11475.0 12297.0 13348.0 13442.0 14422.0 14731.0 17198.0 18336.0 19043.0 19309.0 19554.0 20107.0 20438.0 20759.0 22277.0 23428.0 kHz
Additional frequencies monitored 2006 (ALE/USB)
12626.0 13378.0 14913.0 18194.0 25571.0 kHz
One theory I have seen proposed is that this may be an Indonesian HF net. That is pretty much the book on this mystery. Anyone that has any additional information can contact me at the email address in the masthead.