OrgPad is a universal tool. It is good for planning, brainstorming, presentations, storing information, but it's also good for long-term work like learning for an exam or tracking a project. At first, it'll remind you of Mind Maps but it's so much more!
Dotstorming is a collection of tools that enable collaborative brainstorming, planning and decision making. There are voting boards, a virtual whiteboard and painting tools. Every tool is shareable and works in real time with all the joined participants.