Restoring to 'factory default' kernel settings?

[engelsman]

In my recent kernel reconfiguration marathon, I've experimented with cycling various config options from Off, to Module, to Compile into Kernel and back again. Turning some option off clears out the sub-options too, but turning the option back on doesn't necessarily return the sub-options to their previous state.

What is the easiest way to discover the 'factory defaults' ? Is there a skeleton .config stored somewhere under /usr/src/linux?

(find /usr/src/linux -print | grep config throws up too many matches that I can't see the wood for the trees)