SQLCMD -L :: List all server instances using SQLCMD Utility and output file to .txt

Utilise the following script in the command line using the SQLCMD utility to output a list of all server instances to a text file:

SQLCMD -L > c:\serverlistall.txt

n.b. This example outputs the results on to my c: drive. Alter the file name 'serverlistall' and directory accordingly.