I find that most information on the web repeats itself to a more or lesser degree. My solution may be overkill for many, but maybe something complicated is necessary to deal with the information ocean available to us:
I have a private wiki, in which I write down everything I stumble across that I find even remotely interesting. Thanks to grouping in categories and pages, I can already see what topics I have worked with previously, and I can recognize how much of what I've writing down I'm actually using. This helps me decide whether to dig deeper or let something be. My rough rules are:
- If I don't feel something is worth writing down for later reference, I skip it.
- If I see I've written down something similar previously and I can't remember ever using that, I skip whatever information I'm working with now.
- In all other cases I write down the information I have into my wiki, paying attention to fitting it in with what already is there.
I think there is great value in having so much information accessible to me, so I want to take in as much as possible (my limit is when my head starts hurting - really, if I read or talk about too many topics my head gets this "bursting" feeling). So I use the wiki as my off-load area, so I don't have to juggle everything inside my head, and I can put off things for later when they could be more relevant.