> Good catch Sphero!  I did not realize that an offset voltage was coming
> from the T+ lead until after reviewing the block diagram of the 6675.

Although you are currently using a Maxim part, you might like to look
through the Linear Technology datasheets and application notes.

AN28 - very good looking application note which discusses accuracy and
        sources of error, along with methods for doing high accuracy
        isolation of thermocouples. Based around the LT1025 compensator
        chip, but has wider application.

DN302 - Design Note discussing robust thermocouple interfaces built around
        the LTC2053 instrumentation amp. Again using an LT1025 compensator 
        chip.

LT1013/4 - Dual/Quad precision op-amp with a number of circuits on the
        datasheet for using a single quad op-amp with one section as the
        cold junction compensation reference, and the other three sections
        to sense 3 thermocouples before using a mux. Also has circuits for
        hot wire anemometer and liquid flow sense (I should have remembered
        these for the recent discussion where someone wanted airflow
        measurement)and strain gauge signal conditioner.

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