select t1.owner,t1.tablespace_name,t1.table_name,t1.initial_extent/1024 init_extK,
t1.next_extent/1024 Next_ExtK,
t1.max_extents,count(*) from dba_tables t1, dba_extents t2
where t1.owner=t2.owner and t1.table_name=t2.segment_name
group by t1.owner,t1.tablespace_name,t1.table_name,t1.initial_extent,
t1.next_extent,t1.max_extents
order by t1.owner,t1.table_name
/
select t1.owner,t1.tablespace_name,t1.index_name,t1.initial_extent/1024 init_extK,
t1.next_extent/1024 Next_ExtK,
t1.max_extents,count(*) from dba_indexes t1, dba_extents t2
where t1.owner=t2.owner and t1.index_name=t2.segment_name
group by t1.owner,t1.tablespace_name,t1.index_name,t1.initial_extent,t1.next_extent,
t1.max_extents
order by t1.owner,t1.index_name
/
select t1.tablespace_name, t1.segment_name, t1.initial_extent/1024 init_extK,
t1.next_extent/1024 Next_ExtK, t1.max_extents, t1.status, Count(*)
from dba_rollback_segs t1,
dba_extents t2
where t1.segment_name = t2.segment_name
group by t1.tablespace_name, t1.segment_name,t1.initial_extent,t1.next_extent,
t1.max_extents,t1.status
/

Look for places where count(*) = t1.max_extents.