So there are a couple of interesting new features in the latest Oracle DB version, which is 12.1.0.2.

1) In-Memory Columnar Option — Some more info here at Ludovico Caldara’s blog: http://www.ludovicocaldara.net/dba/db12c-in-memory-overview/

2) Advanced Index Compression — Info here at Richard Foote’s blog (along with a series of great articles on indexing in Oracle): http://richardfoote.wordpress.com/category/advanced-index-compression/

I will be looking into further research on both of these options — particularly the in-memory columnar option — and will try and post something in the next few weeks or month (going to be really busy at least the next two weeks.)