Earlier this year I took a deep dive into APL (something I'd been meaning to do for a while). With Dyalog APL and the APL mode in emacs, typing these things in is pretty easy and becomes natural if you're already a touch typist.

For instance, iota is just `.i`, rho is `.r`, etc. Some are more natural (like that) others are arbitrary but logically consistent, like take and drop are next to each other on the keyboard.

After a few days I felt like I could type most programs without having to think about where keys were. Admittedly, I've lost it all now since I haven't touched it for a couple months. If I actually stuck with it for more than the 4-6 weeks I did I imagine I wouldn't have lost it so quickly.