I'd like to call myself a very big fan of OPT Spaceplane Parts and give much thanks to @K.Yeon for starting this mod, @stali79 for maintaining it, and @Mycroft for confirming that there are others who really, really love this mod. Your ship doesn't have to be built entirely using this mod, just most of it or the most important parts. Come on then, show us your stuff. Spoiler contains old OP content.