Be more like 20 x HDDs in RAID-6, over 2 controllers each with 533 MB/sec (ideally 800/1066 MB/sec+) PCI-X (100/133 MHz x 64 bit wide) interfaces on their own (not-shared) PCI-X tunnels.... and even then I have my doubts when streaming just one file.
Bearing in mind you'd a need 'more than' 10 Gbps network interface (eg: 2 of them), also on their own tunnel(s), and a machine at the other end either decoding some very high resolution / uncompressed video, or with enough disk subsystem write performance to keep up with the ability of the above.
Costs would be quite high, but I suspect it has already been done.
http://store.sun.com/CMTemplate/CEServlet?process=SunStore&cmdStartWebConfig_CP&familyCode=SE6920&baseSelected=0
Pretty expensive for 'just 4-TB of Capacity', but likely upgradable to 33-TB or more, even then doubt the network interface is fast enough.
A 'cheap' cluster of 8 machines, all using Dual-Gigabit Ethernet and 160 MB/sec+ per machine would be able to do 'similar' workloads for a fraction of the US$160,000+ of the above machine.
At 1 GB/sec all my storage would fill up within 60 minutes.