Imagine that cheapo IDIE drives could be bought soon with 100BaseT and not so soon with GigEth over copper connecters. Linux on the disk drive is not as far fetched as you might think - the drives already have two processors out there, the analogue thing that runs the arm and the more normal thing that manages the cache, does any protocol, whatever. Lift the existing normal one, drop in a Celeron, add a little memory and let Linux manage the cache. And run STP, HTTP, NFS, SMB, etc. OK, now image a nice little industry springing up around this.
People make money by putting all the pieces together and selling 'em.
The Ethernet card people start noticing. 3Com comes out with an STP GigE card that does one channel of STP in hardware. Next they come out with 100baseT cards that do 1 channel. Next they have multi channel GigE cards. Next a multi channel 10 GigE card.