TreeSheets

TreeSheets is a tree-oriented, hierarchical spreadsheeting program, used to brainstorm or build structured data. It's written in C++ and its interface is powered by wxWidgets, which allows it to be multi-platform. It's available under the ZLIB license.

Keyboard Shortcuts

Shift + Enter
Adds a new cell inside/under the current cell.
Ctrl + Mouse Wheel
Zoom in/out.
Shift + Mouse Wheel
Increase/decrease text size inside currently selected cell(s).