As for Google Reader, I have more than 1,000 feeds (I’m a consultant and blogger, so it’s actually part of my workflow). I have a “must read” folder, and the rest are organized in topical categories (i.e. Fashion, Humor, Tech, Politics, Blogging). I use these categories as secondary gauge of what to read if I don’t have time — i.e. I don’t read politics or fashion categories unless I have time.

As for Twitter, I like to run Twhirl with Growl notifications on. It plays different sounds/has different colors depending on whether it’s a normal tweet, a reply, or a direct message. Twitter is also an important part of my workflow — it’s great for getting immediate feedback on all sorts of things throughout the day and to assist others (connections which have led to all sorts of opportunities outside of Twitter).

You can get stats about your tweets here: http://www.tweetstats.com