kdiff3
Beyond Compare
WinMerge
Meld
Araxis Merge
DiffMerge
P4Merge
Devart Code Compare
MindManager
Xmind
MindMeister
Coggle
FeatureMap
Idea Market
Viima
Stormboard
kdiff3
MindManagerBeyond Compare - Beyond Compare allows you to compare files and folders.
Xmind - Xmind is a brainstorming and mind mapping application.
WinMerge - WinMerge is an open source differencing and merging tool for Windows.
MindMeister - Create, share and collaboratively work on mind maps with MindMeister, the leading online mind mapping software. Includes apps for iPhone, iPad and Android.
Meld - What is Meld? Meld is a visual diff and merge tool targeted at developers.
Coggle - Coggle is a simple, beautiful, powerful way of structuring information.