As today's headlines swirl with lurid allegations of securities fraud, daily reports of investigations and indictments, and the pleas of swindled investors for justice (and, to be sure, pecuniary recompense), we are mindful that Rule 10b-5, long the ultimate weapon of prosecutors, regulators, and private litigants, subdivides offenses under the federal securities law into three, broad categories: employing a "scheme" to defraud; "mak[ing]" a material misrepresentation or omission; or engaging in "any act" which "operate[s] as a fraud or deceit." 17 C.F.R. §240.10b-5. See also 15 U.S.C. §78(j).