We found this really cool piece of code called CopyForce in Google code the other day which lets you:
Copy your Salesforce org objects (tables, indexes) into Oracle or any other RDBMS, yes you can!
The code I believe is freely available. But not to lose time I used the GUI which is available with trial a license of 30 days from CAPSTORM. In this post I want to quickly show you how you can copy your whole Salesforce org dev or prd with its data into Oracle, then do whatever you like with it.
Installing CopyForce with CAPSTORM (more...)