Unloading the same tables with CoSort's Fast Extract (FACT) v1 for HP-UX, piping these to flat stream sorts and joins in CoSort V8's SortCL tool, and then piping the result into SQL*Loader built the same joined table in 18 minutes (or, ~1/3 the time of the above on-line method).
In 2007, on an HP t5500 Intel Core Duo with 2GB of RAM, Oracle 10Gi's SQL*Plus built a new, 1GB (25-million row) ordered table in 49 minutes.
FACT v2 for Windows's unload results were piped to CoSort’s V9's SortCL tool, which pre-sorted in parallel to feed a direct path load. The same new sorted table was built in 7 minutes (or, ~1/7 the time of the above on-line method).