Dealing with the IRS

[Update 6/13/2012: that interest charge that made no sense was eventually removed]

I arrived back from a little traveling, and found an notice from the IRS.  For those not in USA, the IRS is the department of government responsible for collecting taxes.

A message from the IRS is usually not a friendly greeting.  And this one was no exception.  It demanded that I pay up a chunk of money real soon, or else.