Mention firewire, and a SAN is not the first application that normally springs to mind. Firewire (IEEE 1394) is...
a serial bus (400 or 800 Mbps) that is usually associated with peripherals, especially on the Macintosh. Yet at least one company makes a firewire SAN and it has established a firm foothold, albeit in a very limited market.
Firewire storage products are not unknown. Several companies make firewire RAID arrays that connect to Macs through those computers' built-in firewire port. Micronet's SANCube takes the idea one step further. It is a simple SAN in a box that costs $1500 and supports up to four users in a workgroup. SANCube is limited to cable runs of 15 feet or less.
This is odd, but it makes sense in the graphics and video markets. Graphics arts and video are Mac strongholds where the files tend to be very large. That makes collaboration over a conventional LAN difficult because file transfers are slow. The block-oriented nature of SAN transfers works especially well in this environment because the block sizes can be very large. A SAN appliance like SANCube works well for shuffling files between three or four editors or artists working on the same project without the expense and complexity of a conventional SAN.
This not ever going to be a replacement for a Fibre Channel or IP SAN, and it is not perfect even in its limited world, since the product can't handle uncompressed video, but it is still a useful SAN solution to a particular storage problem.
Rick Cook has been writing about mass storage since the days when the term meant an 80K floppy disk. The computers he learned on used ferrite cores and magnetic drums. For the last twenty years he has been a freelance writer specializing in storage and other computer issues.