Soliciting answers to: What novels or short stories stand out in your memory as “weird”?

I’m soliciting answers to the following question:

What novels or short stories stand out in your memory as “weird”??

I’m doing this in order to put together a “mind meld” (inspired by http://www.sfsignal.com Mind Melds) blog and wiki article based on your answers to this question (inspired by this question posted on Facebook by my friend and fellow writer, Sherlonya).  Feel free to answer with as few or as many novels, short stories, etc as your patience and/or interest  dictate.  If you are inclined, I am also interested in the reasons behind your answer(s).