Harry is in the forbidden forest, standing in front of Voldemort, about to give up his life. The book states "...and Harry thought inexplicably of Ginny, and her blazing look, and the feel of her lips on his--".
Now, a basic reading of this moment and people would think Harry's last thoughts were of kissing Ginny. Those who ship Harry with someone other than Ginny, will have his last thoughts be of that girl. For example, Harry and Hermione shippers, via the use of screen caps from the movies, will have Harry's last thoughts be of her.
However, what if there was more to this moment than meets the eye? Ginny's full name is Ginevra, which is an anagram for vinegar. Thus we have vinegar touching Harry's lips.
New International Version (NIV)
29 A jar of wine vinegar was there, so they soaked a sponge in it, put the sponge on a stalk of the hyssop plant, and lifted it to Jesus’ lips. 30 When he had received the drink, Jesus said, “It is finished.” With that, he bowed his head and gave up his spirit.