
Look at the 4053.  This is a triple 2-to-1 transmission-gate analog
multiplexer, with positive and negative power supplies (can be run
from a single-ended supply as well).  With dual supplies, the logic
inputs still range from ground (0 Volts) to VDD.

This is a neat (well, I think so) design for a switchable-polarity
amplifier:

                 +-----/\/\/\-------+
                 |                  |
                 |    /--------\    |
INPUT -+-/\/\/\--+----| -      |    |
       |              |  opamp |----+------- OUTPUT
       +-/\/\/\--+----| +      |
                 |    \--------/
                 |
CONTROL	---------X (analog switch)
                 |
                 |
                ---
                GND

All resistors are equal-value.  When the analog switch is closed,
the amp is inverting-gain-of-one.  With the switch open, it is
non-inverting-gain-of-one.  You can clean up the circuit to trim
out input offset current if this hurts the balance (this would show
up as carrier feed-through).

For high frequencies, the slew-rate of the opamp might cause problems,
especially if it isn't symmetrical (and it usually isn't).
