One of the first mindmapping Web 2.0 applications that I tried awhile back was MindMeister and it continues to be one of the leading online mindmapping applications available. Just today MindMesiter released version 3.1 with lots of added features. One of the features which I feel will be a welcome addition is the ability to add relationships to your map. MindMesiter calls these graphic cross connections which are easily added by clicking on the Connect button on the Tool bar. You can see in the map below how I added the green connection arrow from one node to another one in the map. In Version 3.1 it is now possible to alphabetize the nodes and so that they are sorted alphabetically. If an individual who has been invited to collaborate on the map but has not yet entered the map a coffee cup icon will appear and by clicking on the coffee cup icon you can "nudge" them to participate. It has also just gotten a lot easier to take your maps offline. No longer do you have to wait for endlessly for all your maps to synch when you go to offline mode - a new dialog allows you to choose which maps you want to take offline. Very useful if you have a lot of them!So check out MindMeister and sign up for a free account. You will also find it easy to embed yourMindMeister maps on your website or blog to communicate your ideas. Below is an actual map that was created with MindMesiter that you can interact with. Let me know what you think.