I have three, go-to apps and programs I use on a daily basis for just that:
Evernote-Hands down, my favorite app for organizing. Not only do I have it installed on every computer I have but on my mobile devices as well. With it I can organize everything I am doing into notebooks and notes. On the web I have the Clipper installed so I can snip quotes, references or parts of blog posts that I want to come back to. Best part? All the annotations come with it so it makes the citation later much easier. From my phone I can add to or edit my notes, insert photos or audio. No matter where I am or what I come across I can add it to my notes and notebooks in Evernote. (I wrote some posts recently about how I am using and ways others are using it as well. You can see them here and here.
ReadItLater-This is another app/program that I have everywhere. Believe it or not I do a lot of my researching on Twitter. Either following a hashtag or asking people to send me stuff. Often times I don't have time to look at everything as it is coming in so that is when I can ReadItLater. With this browser extension I can, with the click of a button mark the site as something to read later. I can search by tag or key word and since I have it installed on my mobile devices I can read my saves when I have a moment or save something to my list when I am out and about.
Diigo-This is another place I save web resources. Again with a browser extension I can take the items I am ready to permanently save and add them to my Diigo list. Oh and I can use the various tools there to annotate and mark up the pages and add any notes. I add tags to organize them and I can share all my saves with a link or two. If you are an educator you get even more perks like the ability to create accounts for your students, sharing lists of sites easily and creating groups so students can share resources.
Of course there are lots of other ways to curate content. Even using something simple like a Google Form or Doc could work. I believe the thing to consider when curating content is how are you going to have access to it. I like to be able to access my content anywhere and from any type of device, easily. Thats why Evernote, ReadItLater and Diigo are my go-to apps and programs for curating digital content.