Multiplayer games

Hi,

I am currently looking into developing some realtime multiplayer Flash games, and, are looking into possible solutions for this.

Currently I know of:
Macromedia Flash Communication Server & Flash Remoting

Araxa Fortress

Does anybody of you know any other solutions?
And, do you have experience with those above, I would appreciate some advantages/disadvantages.

Thanks a lot in advance!

Regards
Mads

Ps: I’m not sure this is the exactly right room for this question.