Most people know about Trello, a hugely popular organization tool based on the Japanese KANBAN model, in which you move a card from column to column. I used it to organize and record all the tools for this site, and I use it to keep track of all my development tasks and marketing ideas, and it also makes a great funnel for fundraising or sales, as you can move a person from one column to the next as they go from cold lead to interested to closed, and so on. Trello is a super flexible and useful tool. Tons of API integrations too.