Impressive idea and implementation. I love that you're going for vi keybindings. Lots of possibilities. You could add a popup that comes in when user presses '

Impressive idea and implementation. I love that you're going for vi keybindings. Lots of possibilities. You could add a popup that comes in when user presses ':' to allow macros. I'd prefer it if you went with 'a' being to edit the current line, and puts the cursor at the end; 'i' to edit line with cursor at beginning, and to use 'o' for add-new-line-after-current line; 'O' to add the line before. If you could turn this into a powerful text editor that would be really neat. Another thing that might be useful is an authentication mechanism that tries to proof against the most obvious internet-cafe afflications (keyboard grabbers, that sort of thing).