I've always had great, pleasant conversations with my CBP officers (is that the correct term?). I remember having a long chat with one of them (there was no line) about Google Books and how his wife loved ebooks. Another talked about his Android phone. Didn't start out with that of course, but usually once they realised I worked for Google it was off to the races. Being a native English speaker (Brit) and entering via SFO probably had huge amounts to do with it as well -- just wanted to point out that sometimes they can be pretty nice people and you can have a friendly conversation!

(On the flip-side my husband was very nearly deported because the border agent at LAX found my Safeway card in his wallet when he was re-entering on a visa waiver. Agent told him if he'd come along later in the day it would have been over, but he was the first borderline case and seemed like a nice guy.)