SQL-Server: Is there a SQL script that I can use to determine the progress of a SQL Server backup or restore process?

I found this sample script here that seems to be working pretty well:

SELECT r.session_id,r.command,CONVERT(NUMERIC(6,2),r.percent_complete)
AS [Percent Complete],CONVERT(VARCHAR(20),DATEADD(ms,r.estimated_completion_time,GetDate()),20) AS [ETA Completion Time],
CONVERT(NUMERIC(10,2),r.total_elapsed_time/1000.0/60.0) AS [Elapsed Min],
CONVERT(NUMERIC(10,2),r.estimated_completion_time/1000.0/60.0) AS [ETA Min],
CONVERT(NUMERIC(10,2),r.estimated_completion_time/1000.0/60.0/60.0) AS [ETA Hours],
CONVERT(VARCHAR(1000),(SELECT SUBSTRING(text,r.statement_start_offset/2,
CASE WHEN r.statement_end_offset = -1 THEN 1000 ELSE (r.statement_end_offset-r.statement_start_offset)/2 END)
FROM sys.dm_exec_sql_text(sql_handle))) AS [SQL]
FROM sys.dm_exec_requests r WHERE command IN ('RESTORE DATABASE','BACKUP DATABASE')

If you know the sessionID then you can use the following:

SELECT * FROM sys.dm_exec_requests WHERE session_id = 62

Or if you want to narrow it down:

SELECT command, percent_complete, start_time FROM sys.dm_exec_requests WHERE session_id = 62

Here's a simple script that generally does the trick for me:

SELECT command, percent_complete,total_elapsed_time, estimated_completion_time, start_time
  FROM sys.dm_exec_requests
  WHERE command IN ('RESTORE DATABASE','BACKUP DATABASE')