  An alternative approach to the calculation of tunneling actions, that control
the exponential suppression of the decay of metastable phases, is presented.
The new method circumvents the use of bounces in Euclidean space by introducing
an auxiliary function, a tunneling potential $V_t$ that connects smoothly the
metastable and stable phases of the field potential $V$. The tunneling action
is obtained as the integral in field space of an action density that is a
simple function of $V_t$ and $V$. This compact expression can be considered as
a generalization of the thin-wall action to arbitrary potentials and allows a
fast numerical evaluation with a precision below the percent level for typical
potentials. The method can also be used to generate potentials with analytic
tunneling solutions.
