Here are some common sql server default ports used:

SQL Component	Port (TCP -default or UDP )
SQL Service	1433
SQL Server DAC (Dedicated Admin Connection)	1434
SQL Browser Service	1434(UDP)
SQL Monitoring	1444
SQL Server Analysis Services Redirector	2382
SQL Server Analysis Service	2383
SQL Server Reporting Services	80
SQL Database Mirroring	5022

By default, the DAC only listens on the loop-back IP address (127.0.0.1), port 1434. If TCP port 1434 is not available, a TCP port is dynamically assigned when the Database Engine starts up. When more than one instance of SQL Server is installed on a computer, check the error log for the TCP port number.

P.S.
1) check this dmv for more informations
select * from sys.dm_exec_connections

2)
 sqlcmd –S127.0.0.1,1434

3) enable DAC:
use master
go
sp_configure 'remote admin connections', 1
go
RECONFIGURE;
go

4) 
sqlcmd -S127.0.0.1 -E -A
-A means dedicated administration connection
-S should not contain port, why?

5)
you can shoutdown server from  sqlcmd, just like Sybase
shutdown
go

6)
isql is the baby from Sybase ASE
osql is newer than isql
sqlcmd is newer than osql
powershell is newer than sqlcmd



Reference:
1) http://joshrobi.blogspot.ca/2008/02/sql-server-default-ports.html
2) http://sqlbuzz.wordpress.com/2011/08/09/sql-server-default-ports/