Whatever Happened to the Pony Express?

I recently received a letter from the IRS stating that I owed $30.19 in penalties and interest even though I had paid my tax bill in full. First off, it's very interesting how they calculate penalties and interest. They charge you interest at the rate of 4.50% against the amount owed for filing late and then another 0.50% against the amount owed for paying late. That, of course is just the penalties. Then you have the interest at 6.0% which includes not only the amount of tax owed, but also the penalties.

I've got my Certified Mail Receipt, dated April 12, 2005 so I'm all set. I call up the 800 number to figure out what is going on. Apparantly, they can get rid of the penalties, but not the interest. So I gather all my data to send out a letter to the IRS and found out:

Your item was delivered at 11:14 am on April 25, 2005 in SAN FRANCISCO, CA 94120.

Here is what happened earlier:

• ARRIVAL AT UNIT, April 24, 2005, 11:07 am, SAN FRANCISCO, CA 94188
• ACCEPTANCE, April 12, 2005, 1:46 pm, AUBURN, CA 95603

Apparantly it takes the USPS 10 days to deliver a letter from Auburn, CA to Sacramento, CA! This is a distance of about 180 miles give or take a few depending on where you're going.

All should be well once the IRS receives my letter, but I'm left wondering just which mode of transportation the USPS used to get my letter there. The current theory is wheelchair.