Ask HN: How do your organize your knowledge base?

Each day I discover, learn and enjoy some new information/aspect about the world while reading books, articles, comments, newspapers or discussion boards such as HN or Metafilter. Sometimes parts of it are good - say comments or sections in a HN thread/article or certain paragraphs in a book. Other times the whole is good - say a beautiful article in NYT that I like to capture along with my thoughts that will help me recall and enjoy the whole article later. Yet other times, I could find useful tips, any kind - technical, financial, spiritual, career or related to aspects of life.

All this information is certainly disjoint, covers multiple topics and very little of it is immediately useful. Unfortunately I can't seem to figure out a way to organize it. I have tried a number of techniques/tools - evernote, delicio.us, pocket.com, clipboard.com, keeeb, bookmarks, sending mails to myself, mindmaps, highlighting, tagging, text files stored on github, writing mails to myself and so on. But as time passes the notes/boards/links keep on increasing or I lose discipline/interest to maintain it and so I forgot what I have read, learned or collected. When I need something, I get the feeling that I know about it or have done it before but can't seem to recall the details - so i have to start search again. It's embarassing, frustrating and disappointing at times. I often wonder when people posts old links or recall wonderful information on HN threads that they read years ago - how do they do it?

How do you effectively summarize, organize and recall your knowledge base - the information/experiences that you collected over years, processed and digested?