It started innocently enough, surfing the App Store for free tools that seemed interesting or worth my time; Stanza has free books (classic sci-fi I never had the chance to read in high school), and the Amazon Kindle for books I buy; Facebook on the iPhone is ok, good as a reader, and I like staying in touch with friends and relatives. Sad, I won't write a note or pick up the phone, but I'll check relatives' FB page every day. I'm a reader - I don't stand in line or wait for appointments without something to read, and the iPhone is significantly smaller, lighter than any paperback, and holds so much more.
And then I downloaded Twitter, and started following business and technology gurus, expanded to follow writers and musicians I like, TV/Movie folks (MythBusters, Whedonverse and BBCA shows) and other tech writers in the STC.
Twitterific has a "Nearby" feature, to see tweets from people in my neighborhood - mostly sad tweens or angry people venting - we have such small lives, some of us...
And then there are the exceptional tweets - wise, inspirational, joyful, insightful. So worth it to sift through the mundane for the gems.