Brainstorming

There are a number of different apps for smart phones or computers that will allow you to visually brainstorm (and some let you share and collaborate with others). This type of tool would be useful during the beginning stages of research projects or essay outlines.

Some available programs/apps to check out:
XMind
FreeMind
Mindomo
Mindmeister
Cmap
Comapping (real-time mind map editing from multiple users; ideal for group projects)

Here's a sample screenshot from FreeMind: