I just use a little powershell script to press a key once every 15 minutes or so. I put the rudder hard over so my ship goes in circles around the spot I've chosen, which is well off the regular shipping lanes
$myshell = New-Object -com "Wscript.Shell"
for ($i = 1; $i -lt 10000; $i++)
{
Start-Sleep -seconds 900
$myshell.sendkeys("w")
write-host We have been going around in circles for the last ($i*15) minutes, Captain!
}