Mysterious notepad.exe spawned every morning
The Task Scheduler service lives inside svchost.exe - are you sure you haven't got a strange scheduled task set up?
Solved - it was done via a c:\Windows\Tasks entry. The "Task Scheduler" lived in the particular svchost instance that spawned notepad, and after Tim Robinson's suggestion, I checked the list under c:\Windows\Tasks - and there it was, in an action called "Oracle", with a cmd "c:\windows\notepad.exe c:\oracle.message.txt".
Who placed it there, and why, is a mystery beyond my abilities... as is why it decided to manifest itself only in the last two weeks.