I've only recently downloaded XMind, but so far it looks like another good mindmapping option. You can find out more about it, and download it yourself, from the XMind website.

There is a free version, and a "Pro" (subscription) version, and both include an online account to allow sharing of your mindmaps with other users. It appears the most significant differences in the two version include additional file export options and a presentation mode in the Pro version. You can see the full feature comparison here: XMind - XMind Pro.

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After just a short time of playing around with it, my initial impressions of XMind are that it is a good tool. It's got some features missing from Freemind, such as the ability to have 'floating' topics, and a fishbone style mapping option. One of the things that Freemind does that XMind is lacking is the Flash export that allows you to create an interactive mindmap to put up on your website. XMind does, of course, have the sharing feature via their website, but the shared file is more like a static image - it's missing the ability to collapse/expand branches that's available with the Freemind Flash export.

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