how to find sql id of a long running sql in oracle

Sql for finding out sql id etc details of some long running query. Often useful for sending kill/monitoring instructions to DBA friends..

select distinct t.sql_id, s.inst_id,s.sid, s.serial#,s.osuser, s.program, s.status, t.sql_text

from gv$session s, gv$sqlarea t

where s.username = '<USERNAME>'

and s.sql_id = t.sql_id

and t.sql_text like '<%provide a segment of sql to identify it%>'