Sun Fire X4500 (Thumper)
The Sun Fire X4500 is nicknamed the Thumper for a reason: 48 SATA drives in a single 4U chassis accompanying a dual-Opteron server with two PCI-X slots. There's no hardware RAID, however, and running anything but Solaris with ZFS is going to artificially hamstring the box. It's not going to supplant the SAN anytime soon, but the X4500 will certainly make waves.
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