There are few commands in chat when /help is sent, which are not described in http://www.skype.com/go/help.chathelp
What do they mean?
Solved! Go to Solution.
/golive - starts a call (works also with more than 25 people, so its a quite usefull command)
If you set a token, you will get an link that you can send to others, if they click on it they will join the call.
/invite - invites somebody to the gruop (kinda obvious o.O)
/fork - creates a new Skype group with the same members, exept the ones mentioned
/undoedit - undos the last edit at messanges (kinda obvious again )
/get uri - gets an link to the skype group
There are a lot of not mentioned commands in the official list, you'll need A LOT off googling if you want to learn all of them, but there are also some commands, that are useless by now.