Raton was a mouse-to-midi continuous controller for the Linux platform I wrote in 2005. It uses alsa midi, was written with Glade2 and requires GTK2.4+ libraries (which are OLD).
The original webpage was linked from the linux-sound.org page (still is, I think, but that page no longer exists), but never received widespread use. I've upgraded the source enough that it will make & compile in Debian 10 (Buster) stable, so it should currently (July 2020) build for most distros. The README txt file in the src directory has more info.
It may be little more than a historical footnote, but I felt the source needed a home.
Also -- it still works very well. Not fancy, but useful.