I have had this peculiar problem for years and tried many tools to solve it, but so far none were satisfactory.
I read a lot of blogs, social sites, etc. and regularly encounter very interesting pieces of information that I know could be useful for me later and I want to preserve. The problem is that by the time I may need them (probably months later) I completely forgot where I have seen that information and how exactly this site was called and what it was about. Only thing I remember is that there was this really great article that is relevant to what I'm doing now and I made a note to myself to get back to it when I will be doing that but that's it. Very irritating.
I tried using bookmarks aggregators like Delicious, but it doesn't solve the problem completely, since I have by now more than 1000 bookmarks there and only way I can find anything there is the tags - but I regularly discover that tags that I used when I saved the info aren't the tags that I'd look under when I need it! For example, I stumbled upon a great site with free pictograms and thought - aha, I like it and it'll work great if I make presentation about X, so I file it under "free pictograms" - and in 3 months I am making presentation about X and try to find the site where I've seen these nice icons - but the tag "icons" shows nothing! Neither does "pictures"! Hmm... I can't use the thesaurus each time I find something useful, right?
So, is there a better way to manage these pieces of information?