Little Sisters Book and Art Emporium v. Canada (Commissioner of Customs and Revenue), 2007 SCC 2
Click here [3] to link to the full judgment.
(Advance costs / prima facie merit / impecuniosity)
Advance costs: Only "rare and exceptional" cases will be entitled to advance costs; this is a high bar.  A case must be sufficiently special that denying advance costs would be contrary to the interests of justice, the matter must relate to the individual and the public at large, and the applicant must have explored all other funding options.  If costs are granted, the litigant loses some freedom in controlling the case.  In this case, the Court found that Little Sisters did not pass the high bar and dismissed the appeal, thereby denying the application.
Majority/Concurring/Dissent: 5/2/2