Hand tremors from Parkinson's disease and Essential Tremor can make using a computer mouse nearly impossible. The cursor not only flies everywhere but accidental clicks also result in unexpected actions being taken. This of course is extremely frustrating.
After my grandfather was diagnosed with Parkinson's in 2003-2004 I saw this first hand and consequently set about solving the problem in software. SteadyMouse was born.
The software contains both an anti-tremor motion rejection algorithm to keep things stable, and an accidental click blocking mechanism to only let through intended clicks.
The last two years were spent on a massive upgrade for a commercial version (in addition to the original free version).
Here's a gif of the filtering in action: https://twitter.com/steadymouse/status/890794753637326848
The main site is here: https://www.steadymouse.com/