OpenEditor
OpenEditor is a text editor for Oracle developers and DBAs
... and larger than 100MB), virtually no line size limit (2GB), columnar text selection and editing (like in UltraEdit), match searching for PL/SQL (BEGIN/EXCEPTION/END), regular expression in text searching and replacement, keymap customization (change custom.keymap).
The major limitation is lack of support for UTF or UNICODE and I no plans for this in the nearest future.
Check for the latest news here: http://www.sqltools.net/cgi-bin/yabb25/YaBB.pl?board=sql_status