Have you played with Oracle external tables yet? They are perhaps one of Oracle's more overlooked features. I'm mostly interested in DBA/tuning uses of external tables at this point.
When they first came out in Oracle9i I wrote an article in SELECT for IOUG-A on using external tables to read your database alert log from within the database. I'm now using external tables to load the results of 10046 traces into the database (I have a presentation at OAUG on this topic). The results are interesting and fun to play with, that's for sure.
I'm really just starting to play with the 10046 traces in Oracle. I'm trying to figure out some different reports and different ways to play with the data. If you have any ideas, let me know. I'm also struggling with one part of the 10046 loads, that is getting the SQL statement to load into properly into the external table. I've tried several different ways, but so far it's not working like I think it should. I've not had time in the last couple of weeks to work with it again though...
So, I'm curious what kinds of DBA/development/tuning things have you done with external tables?