Oxymorons

"Once Again" is an oxymoron, is it not? It's part of the tradition of putting two terms together that have no business being anywhere near each other.
You may remember such classics as... jumbo shrimp, deafen-ing silent, military intelligence, sweet sorrow, organized chaos, Icy Hot, nondairy creamer, mutual differences, mandatory options and head butt.
Any other additions to the club?