А емакс так может?

Сначала демка онлайн терминал с Vim http://gateone4.rs.liftoffsoftware.com/



паста со слешдота

Version 1.1 of Gate One (HTML5 terminal emulator/SSH client) was just released (download). New features include security enhancements, major performance improvements, mobile browser support, improved terminal emulation, automatic syntax highlighting of syslog messages, PDFs can now be captured/displayed just like images, Python 3 support, Internet Explorer (10) support, and quite a lot more (full release notes). There's also a new demo where you can try out vim in your browser, play terminal games (nethack, vitetris, adventure, zangband, battlestar, greed, robotfindskitten, and hangman), surf the web in lynx, and a useful suite of IPv6-enabled network tools (ping, traceroute, nmap, dig, and a domain name checker