I remember using it around the time they switched names. Although I barely ever used the collaborative features, SEE's multi-cursor editing capabilities were like magic. Yeah, other editors let you edit multiple lines, but SEE was the first editor I'd used that gave you multiple distinct cursors, rather than giving you a single vertically stacked cursor. Top that off with OSX's default emacs keybindings, and you had a super simple, but incredibly powerful editing experience.

I eventually needed something cross-platform and switched to Sublime, but I still have very fond memories of SEE.

That’s right! I’d forgotten how utterly amazed I was when I discovered multiple cursors and how useful they were. I don’t think I’ve ever encountered that feature anywhere else.

Doesn't sublime text have multiple cursors?

I came late to the party (I got hold of it I think in 2005) and I had the same experience.