I'll submit the following six from an older......errrr....I mean more mature perspective.
Rocky Bridges - Because he was brought in to take Grady's 2B job. Also because we gave up Joe Adcock to get him.
Milt Pappas, Jack Baldschun, and Dick Simpson - The "has been", the "never was" and the "never will be" we got for Frank Robinson. And they had the gall to give Robby's No. 20 to Simpson.
Woody Fryman and Dale Murray (I think) - The roster filler we got for Tony Perez.
Pappas was especially galling to me. One night at Crosley Field we were seated behind home plate. Freebies left for us by Larry Dierker who had played in the lower minors with a friend. Anyway Pappas, the Red's starter was bombed and yanked in the first inning. It wasn't five minutes (I doubt he even showered) before he was in deep conversation with Marvin Miller a couple rows in front of us showing no interest at all in the on field activity. I believe to this day that he tanked his start so he could discuss union business with Miller. Then again.....I could be wrong.