Harry Potter and the Deadly Heller by DianeCastle
http://www.tthfanfic.org/Story-27958/DianeCastle+Harry+Potter+and+the+Deadly+Heller.htm
Awesome story that combines BTVS and Harry Potter perfectly. I usually do not like Harry/Ginny pairings as she always seemed lack character Here the author shows just what Ginny is capable of from the moment she hears the words "Are you ready to be strong?" She uses her new powers immediately and later flat out tells Harry he is not doing this without her. She is more then his equal and will stand at his side. The action is amazing and the story flows consistently. She has slayer dreams to warn of trouble even though no one believes the first one. The getting the cup was pure thrill ride. A story definitely worth re-reading.