set verify off
COLUMN a new_val thisuser noprint
COLUMN b new_val todaysdate noprint
select USER a,
	TO_CHAR(SYSDATE, 'YYYYmmdd_HH24MI') b
from dual;

spool mylog_&todaysdate..log

ttitle "This is my title &thisuser &todaysdate"

select 123 from dual;

prompt Logfile is mylog_&todaysdate..log
spool off

Connected to:
Oracle9i Enterprise Edition Release 9.2.0.8.0 - 64bit Production
With the Partitioning option
JServer Release 9.2.0.8.0 - Production






Thu Jun 21                                                             page    1
                      This is my title SCOTT 20070621_0947

       123
----------
       123

Logfile is mylog_20070621_0947.log
SQL>