Fastmac recently announced a 4x Blu-ray Disc writer for Apple's Mac Pro & PowerMac G5 computers. This tray loading drive writes to single and dual layer Blu-ray discs at 4x and is backwards compatible with standard CD and DVD media.

Fastmac today announced a 4x Dual Layer Blu-Ray optical drive upgrade for Apple's Mac Pro & PowerMac G5 computers. The new 5.25-inch, tray loading drive uses one of the fastest Mac-compatible Blu-ray mechanisms to provide up to 50 Gb of storage on 1 dual or double layer disc, without sacrificing compatibility with standard DVD & CD recordable media. Using a SATA connection, the drive's 4x BD-R DL mechanism allows professional Mac users to burn upto 50GB of data on 1 disc in less than 50 minutes.
Fastmac's 4x Blu-ray optical drive upgrade is available now for a special introductory price of $579.95. Full details can be found here.