FSQL is command line tool that can be used instead of standard ISQL.
It has some enhancements, like commands to import data from csv,
show active connections, insert file contents into blob, making backup
from sql script, color output highlighting, etc.
To list new commands execute

HELP [SET | SHOW | SERVICE];

Short description, some examples, and link for download is here:
http://www.volny.cz/iprenosil/interbase/

Windows only, Freeware.
Any feedback welcome.

Ivan Prenosil