Mozilla Labs » bespinThe Bespin project is building a web-based code editor using the emerging HTML5 standard. The editor is easily extensible with JavaScript and can be used in your own applications or on our experimental hosted service. Bespin Embedded 0.6.1: Syntax Highlighting Rebooted With the release of Bespin Embedded 0.6.1, we close one of the major feature gaps with the pre-Reboot Bespin, taking it up a level
「Safari 5.0.1」リリース、エクステンションが利用可能に 
