This handy little command reminds me by audio when my computer is back online. I just had a 30 minute Internett outage, and it was nice to get right back to my seat when my computer started bleeping out alarms.
for /l %i in (1,0,2) do @ping -n 2 126.96.36.199 2>1>nul && @powershell -command [System.console]::Beep(300,1000)
The for loop defines basically a while(true) loop in Windows. It will run for ever.
If the ping command runs successfully, the powershell command will run a small beep over 1 second.