He kept voluminous logbooks full of weirdly brilliant philosophical riffs.

Later in life, he cheekily donated his brilliant riffs on perhaps the country's most cherished painting - "Las Meninas" by Velázques - proving that even after years of self-imposed exile, Picasso couldn't get Spain out of his system.

All this might seem a little phony, or, worse, crass, but a bite of peekytoe-crab toast ought to stifle your concerns: buttery, salty, with a trace of fennel, it was a brilliant riff on boardwalk cuisine.

A few drawings here, high-key, muscular and subtle at the same time, look like brilliant riffs on de Kooning.

At Second Stage, the endearingly high-strung Desmin Borges played Macedonio Guerra, delivering brilliant turbocharged riffs on ethnic America.

Sam Lipsyte's miserably funny "The Ask" is, among other things, a brilliant riff on this alarming phenomenon.

Pure heaven: nearly three dozen early sculptures, small enough to hold in your hands, and a few drawings, brilliant riffs on de Kooning.

Beating like a stately continuo behind the brilliant riffs of Mr. Hobsbawm's specialized studies has been his vastly ambitious project to write a grand, synthetic history of the "long nineteenth century" stretching from the American Revolution of 1776 to the outbreak of World War I in 1914.

In "Multitude," there is much fancy footwork and theory, intriguing historical asides and intermittently brilliant riffs, but their schematic picture is brutally clear.

For the most part the reader does not yawn through "Pelikan," which has some brilliant riffs as well as some not-so-brilliant ones.