In the recent decision of Docherty v. Minister of Public Safety and Emergency Preparedness, (2012 FC 723) Federal Court of Appeal judge Phelan wrote as the first line of the decision:

“This is a case of a traveller sailing too close to the legal winds. But for greed, this Applicant would not be in Court.”
Mr. Robert Malcom Docherty failed to declare cash in an amount exceeding $10,000 and it was seized pursuant to the Proceeds of Crime (Money Laundering) and Terrorist Financing Act (Canada). Mr. Dockerty was traveling from Toronto Pearson International Airport to Costa Rica when he was stopped by the CBSA (a currency sniffer dog smelled money).  He had in his possession $USD 9880.00 and $CAD 335.00.  With the conversion of $USD into $CAD, he exceeded the $10,000 threshold.
The Bank of Canada rate made all the difference.  On that day, the conversion rate put him over the monetary threshold and the money was seized.  Mr. Docherty knew about the monetary threshold limit for reporting and had made an attempt to stay below the threshold. Unfortunately, he miscalculated.
This should be a lesson for travelers.  It was a costly lesson for Mr. Docherty.  All the cash was seized as forfeit – any he missed his flight.