I spent a litte time doing at least three things which would not have been possible a few decades ago. First, I worked on setting up my course page on the Internet portal at BCIT. Not only was there no Internet, but the very idea of a resource like this where students are expected to access from their homes would have been clearly under the realm of science fiction. On another institute system, I also published the course outline electronically. Secondly, I now provide much more media content than in the past. When I started teaching, any audio materials were provided by publishers on cassette tape. Today, I just provided links for more authentic listening by podcast. In this case it was just a few warm-up summary practices using a few episodes of 60-Second Science by Scientific American. Lastly, I photocopied some materials as handouts. Photocopiers were certainly available at the beginning of my work life, but today I also had a pdf packet sent to my email address for inclusion in the file storage area which students may access.
In conclusion, getting ready for a new class still takes a lot of time but the tasks required have changed immensely.