Steve, found the following when you piqued my curiosity about the Ides of March:

The original Roman calendar, introduced about the 7th century BC, had 10 months with 304 days in a year that began with March. Two more months, January and February, were added later in the 7th century BC, but because the months were only 29 or 30 days long, an extra month had to be intercalated approximately every second year. The days of the month were designated by the awkward method of counting backward from three dates: the calends, or first of the month; the ides, or middle of the month, falling on the 13th of some months and the 15th of others; and the nones, or 9th day before the ides.

I've decided to do "You've Been a Friend To Me" for the friendship between Caesar and Brutus.