The Academy of Science is pretty amazing, although it can get really full on weekends (best get there early if you go). The arboretum in Golden Gate Park is also pretty awesome, and unlike the Academy, free. Both great reference sources if you do a lot of organics.:D Hiking up Twin Peaks is really fun and makes for an…
Grace Cathedral Bring a sketchbook. :) None of this is really 3d related but: The DeYoung, next to the academy of science, is cool if you're into museums and that "old school art" stuff. The ILM buildings look nice, but they're all keycard locked so its more just walking around the Presidio. Though there is a Yoda statue…