Workflowy

For people who think in nested lists and want nothing else on the screen. Workflowy is one long outline of bullets you indent and collapse, which turns out to be oddly good for agendas, reading notes and planning anything with sub-parts. There are no pages, templates or databases to set up first. Its exit is one of the cleanest here: you can export a single bullet or your entire account as formatted text, Markdown, plain text or OPML. The catch is the free plan's 100 new nodes a month, which an enthusiastic outliner can burn through in a week; Pro is $6.99 a month billed annually.