The Microsoft Intellimouse. When I was in school in the '90s, I had to de-gunk mouse rollers almost every time I sat down in a computer lab. A low cost optica

The Microsoft Intellimouse. When I was in school in the '90s, I had to de-gunk mouse rollers almost every time I sat down in a computer lab. A low cost optical mouse for generic surfaces made all that work just evaporate. (I guess that's not strictly software, since it needs a basic digital camera.) https://en.wikipedia.org/wiki/IntelliMouse https://en.wikipedia.org/wiki/IntelliMouse