>      Actually, it was a silicon cost tradeoff that the I2C is slave only.
>      Royalties are due whenever I2C is implemented in silicon.
>
>      Some of the newer devices, such as 17C756, have master mode I2C.  The
>      master mode requires substantilly more logic as well as a baud rate
>      generator to be added to the device, so expect to pay a little more.

Although I have not done it myself, it would seem that the 16C74 can, already,
do most of the work for master-mode I2C if you don't mind sacrificing an I/O
pin.  Simply send the start condition manually, then use the SPI hardware to
clock out 8 bits, then do the acknowlegement by hand, then clock in or out 8
more bits, etc.