Found out about Blu-Ray ages ago...
http://en.wikipedia.org/wiki/Blu-Ray_disc
12 cm, single sided 25 GB (23.3 GiB) 50 GB (46.6 GiB)
12 cm, double sided 50 GB (46.6 GiB) 100 GB (93.2 GiB)
8 cm, single sided 7.8 GB (7.3 GiB) 15.6 GB (14.6 GiB)
8 cm, double sided 15.6 GB (14.5 GiB) 31.2 GB (29 GiB)
About 9 hours of high-definition (HD) video can be stored on a 50 GB disc.
About 23 hours of standard-definition (SD) video can be stored on a 50 GB disc.
On average, a single-layer disc can hold a High Definition feature of 135 minutes using MPEG-2, with additional room for 2 hours of bonus material in standard definition quality. A double-layer disc will extend this number up to 3 hours in HD quality and 9 hours of SD bonus material.
Chris
