There's TeXmacs, which lets you enter mathematics either via point-and-click palettes or using TeX notation. I like it a lot. Downsides: 1. Development seems mo

There's TeXmacs, which lets you enter mathematics either via point-and-click palettes or using TeX notation. I like it a lot. Downsides: 1. Development seems more or less dead. 2. It's not always been perfectly stable. 3. It's kinda sluggish, especially on older slower machines.