Is Team Concert free for teams of less than 10 people?
Yes it is. IBM does that for small teams to compete with Open Source and lower cost alternatives.
YES its free for 10 user and u can setup it with normal tomcat and derby db. But this will be very limited and not recommended for any kind of production code or ALM repo. And only RTC is free. You cannt get Doors or RQM suit with that.
Not exactly. It is free to use in the jazz.net but with the features that IBM provides. If someone wants more features and want to create multiple projects and connect to different databases then TC licenses need to be bought.