Wagner's sketch for the Bridal Chorus from Lohengrin is for sale, at the heady price of $3.6 million. According to the listing offered by the seller, the manuscript was presented by Siegfried Wagner to a friend. It would be interesting to know who received this rather lavish gift.
More: The invaluable Matthew Guerrieri advises that more information can be found in a footnote to John Deathridge's essay on the Lohengrin drafts in Carolyn Abbate and Roger Parker's collection Analyzing Opera. This same Bridal Chorus manuscript went up for sale at Sotheby's in 1988; it seems that Siegfried Wagner gave it to an Italian friend, "Signor Zamboni."