Strangely enough, the "Layla" lick was played not by Clapton. but by Duane Allman--Clapton never played the lick in concert, always leaving it to the other guitar, and he finally re-arranged the song without the lick, which, IMHO, was not an improvement--

Though these guitars apparently went for enormous amounts at auction, I wonder how much anyone would be able to resell them for--