I think I've now seen it all.  There is a guy that analyzes the potential for trades based on currency pair tendencies during certain times of the year.  This information is based all on historical information.  Here is an excerpt:

Directional considerations aside, April does tend to be quite volatile. Consider the following:

The table above outlines the average pip range for the major currency pairs during the month of April from 1999 to 2005.Even though the majors may not tend toward moving in one direction or another during the month, they certainly do move, so short-term traders can expect plenty of profit opportunities.

http://www.tradingmarkets.com/.site/Forex/Commentary/essentials/-50407.cfm