Companies' monthly financial reports may run fine for years, then crash in February of a leap year when software tries to compare Feb. 29, 2012, to a nonexistent Feb. 29, 2011.

WSJ: For Some, All in a Leap Day's Work

So, on January 1st, the fund buys as many jugs of water as it can afford, and sometime before midnight on January 31st, it sells all the jugs, and makes a deal with the supermarket that the supermarket will set aside more jugs for the fund on Feb 1 and hold them for the fund until February 28th.

FORBES: You Say Contango, I Say Problemo

Just days ahead of its fourth quarter earnings results on Feb. 21, e-mails from top management leaked to Bloomberg indicating a bust in February sales.

FORBES: Leaked Emails Indicate All's Not Well With Wal-Mart