Find All SQL Server Instance Running in Local Network

How to list all SQL Server Instance Running in Local Network:
Some time you need to see the List of other running SQL server on your network. It is so simple and easy to call from other application also.

See the example:

-- ######### Query
EXEC master..xp_cmdshell 'osql -L'

-- ############ Result

NULL
Servers:
    (local)
    MAIL_SERVER
    RAGHU
    RAGHU\SQLEXPRESS
    SERVER1
NULL

If you want to get the same list from Command prompt then:

C:\> osql -L

it will show you the same list.