@Byte historic landmarks we have a lot of. there are a lot of themed city tours (more interesting than regular tours, I think) here: https://www.stattreisen-muenchen.de
we have a chaos computer club space in munich https://wiki.muc.ccc.de/public:treffen that might be interesting regarding the hacking scene. but most events there are in the evening or weekends.
landmarks: architectural, I think Olympiapark is most interesting. If you are interested in churches and can stand baroque ostenation, visit Asamkirche (it's small, but ostentatious) in the city center. there are several other remarkable churches (Alter Peter, Frauenkirche, St. Michael) in the city center.
free entry, very good museum: NS Dokuzentrum (nsdoku.de) about the rise of fascism and its influence in Munich, specifically.
good food... don't eat german food. we have good japanese restaurants, persian, ethiopian are also personal faves.