I use
didiwiki for my personal notes. I originally wanted a more robust wiki (MediaWiki) but I didin't want to run a full-blown webserver on my laptop. I sometimes take notes in a small notebook (moleskins are nice) and later transfer stuff to the wiki.
I also use the ScrapBook firefox plugin to save online articles, cut out the unimportant bits, and highlight my favorite parts.
I use google calendar for calendaring and google's rss reader for managing my news.