Zimbra

Zimbra is releasing its service as an open source project - it is a office like suite that runs within your internet explorer, mostly developed using JavaScript (AJAX) . This kind of solution is very sweet for offices , since it does really allow to get rid of the thick clients and run everything put of the network. The email client is very similar to the Outlook Web version, I did not see on the demo how the spread sheet and text processor look like.

A really interesting usage of this kind of solutions if for mobile devices, which are always connected by GPRS, WiMax, Wifi, etc. Once the JavaScript code loads, the bandwidth and latency requirements are not huge since most of the application runs on the client side.