I was just glancing at the docs for the recent release of DBD::Oracle (1.16), when I noticed that it comes with a handy little Tk based explain tool.
If you've installed DBD::Oracle, then you can simply type "ora_explain" and a nice little Tk interface pops up where you can enter your sql, hit the "explain" button, and an explain plan appears at the top, with an explanation in the middle. There are some other options, too.
Handy tool to have if you don't happen to have TOAD or TORA. :)
