Our ads are geographically limited and currently run to cover the basic working day, 7am -7pm.
I suppose because we don't expect anyone to search B2B terms outside these times.
But if no one or only a few are searching for these terms outside these times it would cost us nothing to be 24/7 and we might pick up people working late or early who we might otherwise miss?
Just thinking aloud ...
What does webmasterworld think?