I have, for a while, been looking for and collecting images of San Francisco before the earthquake in 1906. This is currently my favorite image of San Francisco (in any time period) - a nighttime photo of Chinatown in 1904.
In 1906 an earthquake and the proceeding fire leveled much of San Francisco. Its a bit difficult to find images of the city before that quake but as far as I've found nearly impossible to find images of Chinatown before 1906. The entire old Chinatown was destroyed in the fires that raged after the 1906 quake, and was rebuilt in its current location. Because of city laws meant to dissuade further chinese immigration, Chinatown in 1904 was overcrowded and overbuilt and not really considered post card material.
Another of my favorites, as someone who enjoys maritime imagery and the part that sailing plays in the mythos of exploration and adventure. Look at the plated hull on that thing. If that doesn't make you think steampunk I don't know what to tell you!
And finally, here's the steam train that used to run right through Berkeley, where Shattuck Street is now. Its a good reminder of how important and pervasive the steam train systems once were in the area.
Just a little bit of inspiration for everyone. Its easy to forget sometimes that many places possess a rich visual history of photographs if you can figure out where to look for them. Sometimes a great source of inspiration is what your home town really looked like 100 years ago.