Once upon a time, Led Zeppelin were strict about licensing their music to corporations for commercials. The wall came down momentarily when Cadillac used IV’s “Rock and Roll” in 2004. So imagine our surprise today when — while anxiously today’s finale of the Woman’s Canoe/Kayak finals (which the Australians took gold and silver in) — NBC aired a commercial promoting their Olympic coverage using Zep’s “Bring It On Home” as its soundtrack. Supposedly, “Bring It On Home” is the catch phrase for this summer’s Olympics, (with “It” meaning gold medals, which the U.S. is doing quite prodigiously). Here’s hoping they start using “Kashmir” in all their training montages.