I'm a quote junkie. I've collected them my whole life. Whether it's a scrap of paper with an inspiration quote or a list of "funnies" to cheer me up when I'm cranky, I've always considered quotes far worthier of collecting than stamps or coins.
If you're like that, proceed immediately to the App Store and procure http://quotebookapp.com for iOS. It costs $2.99 and is a universal app. (There's no Mac app, but this is why God made Pastebot; you can also e-mail the quotes to yourself or Evernote or export via iTunes.)
Hear something? Read something? Slap it in Quotebook along with a rating, source, and tags, and then you can relax into a quote-lover's paradise. Slice and dice your quotes by source, rating...any way you want.
It's not a complicated app or a complicated idea, but it's worth the $3 to me to not have to search through Evernote, Tumblr, and Twitter to find that HILARIOUS THING someone said a few months ago (quotes can be Tumbled right from Quotebook, too).