Visualizing the City
Google Earth has to be one of the coolest things going for map freaks like me. It works best on a broadband connection and a newer computer though. The really cool part is the 3D buildings layer which includes the downtown areas of most major US cities, including St. Louis. Although it's not 100% accurate, it gives a nice general idea of the form of the urbanscape.
Another, albeit rather buggy tool, is UMSL's Virtual St. Louis City Project, spearheaded by history professors Louis Gerteis and Andrew Hurley. It aims to place historical photos of downtown St. Louis buildings in their proper context, by decade from 1850 to 1950. Some decades work better than others; but the idea is really nifty.
360StLouis.com is less impressive, but has a few ok video tours of downtown and other places.
Apparently MoHist next month will unveil a "virtual tour of St. Louis cultural communities" next month, but I don't know the details. Meanwhile, St Louis Community College at Meramec has a virtual tour of its campus that can be downloaded onto Google Earth.
So even if you can't or don't want to go out and see the city, you can get an idea of what the world looks like from your seat. That's not a substitute for real life experience, of course, but it can be a fun way to spend a few minutes.