Museum of Obsolete Objects.
The Museum of Obsolete Objects is a neat YouTube channel featuring videos about objects like cassette tapes that at one point represented cutting edge technology and are now obsolete. The MOOO isn't limited to 20th Century objects. The list includes things like quill pens and the telegraph. I've embedded the telegraph video below.
Applications for Education
Have students pick an obsolete object then research that object's influence on communication and culture in its time. Then have students pick a currently ubiquitous object like the iPod and ask them to make predictions as to how long that object will be relevant before becoming obsolete.