And also when you are a writer
More recently, footnotes have been employed to postmodern effect: Vladimir Nabokov and David Foster Wallace used them flamboyantly; writers such as Nicholson Baker applied them from a softer palette.
From Nathan Heller's "Save Footnotes" in the New Yorker
Nicholson Baker nods at Nabokov in his Steve Jobs eulogy for the New Yorker:
We’ve lost our techno-impresario and digital dream granter. Vladimir Nabokov once wrote, in a letter, that when he’d finished a novel he felt like a house after the movers had carried out the grand piano. That’s what it feels like to lose this world-historical personage. The grand piano is gone.Read the rest of the piece at http://www.newyorker.com/talk/2011/10/17/111017ta_talk_baker#ixzz1bF6x4se6