Elon musk is single-handedly (of course with the help of his investors and very hard working employees) changing the face of three areas: Automotive, Space transportation, and Energy & Renewables.
Elon musk currently has many patent filings from Tesla; however, one of his earliest focus areas was the internet, and his company Zip2 was one of the earliest forms of internet based yellow pages.
Musk's earliest patent filings focus on the specific area Zip2 was working on. The first patent which has Elon musk as the inventor is US5944769A, titled 'Interactive network directory service with integrated maps and directions'.
This patent focuses on combining a business directory and a map. A user can search the business directory in a variety of methods, including using aspects of the map database (i.e., a radius) to quantify the search. The user can then obtain directions from a specified user location to a selected search result. All of this is conveniently accomplished through a single website access.
Now, wait a minute! This is very similar to what we do with any map service (google maps, bing maps, apple maps) these days! However, this patent was filed in 1996 - way before we had those services.
Another patent filing having Elon musk as the inventor is US6185194B1, titled 'System and method for initiating a telephone call utilizing internet initiation'. It focuses on a method to in which a user provides an input to the computer to initiate a call. The call request data is received at a Web site providing the display, and is relayed over the Internet to a call center. The call center establishes the desired phone connection over the Public Switched Telephone Network.
Almost all websites and applications have a call button these these days! But this was 1997.
These are two of the earliest patent filings from Elon musk.