Something that I have appreciated in both Tübingen and Heidelberg is the ubiquity of books. In these university cities you can find a book store every couple of blocks or so.
In Tübingen, a city I lived in a few months ago, there was a large culture of giving books away for free. I very often saw books sitting on the stoop of some apartment that said Zu Verschenken – basically that they are giving them away for free. This generalized to furniture and other items as well. When people didn’t want something anymore they just put it outside for someone else to take. I should note that this wasn’t always just crap – there are many books you would want to read and furniture that you could actually sit in.
I see this less in Heidelberg, but there is another phenomenon here: city sponsored bookshelves that are outside where people can take or leave as many books as they want. The one right near our apartment pretty much always has at least one person browsing, which is nice to see.