The multiplayer dice roller: http://a.teall.info/mdice
Ok, this is a beta version for now, with minimalist user interface (yep, I love it) and still testing functionality. Google App Engine has its own pitfalls, especially on socket handling. But it looks like running good.
The GUI will be modified by users' requests, but do not expect much =)
A couple of words about how this works.
First of all, you have to create your own room. Then call your friends for join the room. That's all.
Throws are synchronized and everyone in the room will see them.
Well, I know that this simple functionality is not enough to play online. I going to add complete log with simple event cutter, and asynchronous throws: players may throw their dice simultaneously in some sort of situations like "initiative call". So don't be angry on me because this is not done yet =)
Have a fun and look for updates =)
UPDATE for 21 Jan 2016.
I added chat/log. I still thinking about desing and usability, but it's betterd than nothing =)