James Gosling is understandably famous. Although he wrote the first C version of the Emacs editor, I first became aware of him while trying out the Andrew window manager in the mid eighties. The Andrew WM was interesting in that it tiled windows rather than overlapped them, and I rather liked it. Then he designed NeWS (Network extensible Window System) in the late eighties that was built using PostScript (little or no relationship to Display PostScript which was Adobe's idea of how to use PostScript on screens) that was also very interesting. I designed a couple of very simple windowing systems in the early eighties for page display on MS-DOS, and so had some idea of the complications involved.
Now Gosling is mainly known for developing Java. When Java was first announced a couple of us at OCLC jumped at it and started using it. Our main problem was speed. One of our applications decoded Group-4 encoded images for page display and when written in Java it was very slow. One of the main Java developers got interested in it and rewrote it to speed it up some and Keith Shafer (no longer at OCLC) and I went out to California to visit and talk about our applications.
I was in charge of the car, and during the visit went out to move it to avoid a parking ticket. While I was out, Gosling appeared and Keith got to talk to him a bit. I still wonder whether I would have had the nerve to ask him if he would sign my copy of The NeWS book I was carrying with me.
Here's an interesting article by him: Windows System Design: If I had it to do over again in 2002.