Long, long-time followers will know my sordid history with Check Point FireWall-1 and various issues related to network security. I'm all too familiar with how companies can--and do--restrict their users. My employer is no exception. While they have loosened their stance on responsible use of certain applications over the years, one of the fundamental things about the network is that in order to get out to the Internet, you must go through an HTTP proxy.
Enter two new applications I've looked at recently; Yugma and Tungle. Yugma is like WebEx or GoToMeeting. Tungle allows you to more easily schedule meetings across corporate boundaries. Both are exceptionally useful applications.
My acid test for any application is the corporate network. If it can work in our corporate network, chances are, it will work anywhere. Skype is a wonderful example of an application that works everywhere--including on our corporate network. On one hand, I find it scary from a security standpoint, but as a user, I appreciate that it just works.
Some applications fail the HTTP Proxy test. SightSpeed--one of my favorite ways to video chat--simply won't work through the corporate firewall. You can blame SIP for not working through an HTTP proxy, which SightSpeed can't do much about.
Tungle is another one that fails the firewall test, particularly the part that synchronizes free/busy with the Tungle server so your friends can schedule a meeting with you. Other parts of Tungle will work just fine with a regular HTTP proxy. Furthermore, there's no way to even configure proxies into Tungle. The folks at Tungle are aware of these limitations and are addressing them.
Yugma, at least, seems to have some support for HTTP Proxy. It pops up a dialog box after spinning its wheels for a while, realizing it might need one. However, my experience is that I can't make session sharing to work in this configuration.
It's a challenge to work around all the various firewall issues. However, for large-scale corporate adoption of your product, this is a must.