Bluray writers are the latest storage medium. It is deigned to replace DVD-Writers as it can store 25GB of data on single layer bluray disc or 50GB on a dual layer disc. Becuse bluray is new technology it is still very expensive to have mass market appeal. If you need to backup or archive huge amount of data it would make an excellent backup device.
Recommended Bluray Writers:
LG Electronics 14x SATA Blu-ray Internal Rewriter without Software
ASUS BW-12B1ST/BLK/G/AS 12X Blu-ray Internal Burner Drive
Pioneer 15x SATA Internal BD/DVD/CD Burner with 4 MB Buffer BDR-208DBK