For those that sail in the NE on lake Narrabeen there is a nasty dangerous submerged log, approx 80 metres se of the main white buoy. Watched a mate hit it the other day. This thing could do serious equipment damage or body damage. Took the liberty of making homemade / temp buoy ( milk bottle )and attaching to the log, which is marked with "do not remove danger log" all over the bottle. Hoping I can find a more permanent buoy which I can attach to it this week. If your gybing in this se corner take care and avoid the milk bottle!