Honestly, it's hard to say. I don't think I'm driven much by obvious and immediate peer influence, since I can't remember the last time I bought anything... mp3 player, car, clothes, etc. based on any influence from a close friend. I have pretty specific tastes in each of those things, and I tend to buy what I want based on my own criteria.<p>Now how much my tastes - in general - where shaped by the influence of others in an indirect sense, is hard to say. For example, the last portable music player I bought was chosen specifically because it was the biggest device the local Best Buy had in stock that supports Ogg Vorbis. I favor patent unencumbered formats like Ogg, and am trying to get away from using mp3s in general. So, how much did my friends, colleagues, etc. influence my stance as a free software, open standards, open source, etc. ideologue? I have no idea.<p>Same for my last car... I bought a Mazda RX-8 because I like fast, sporty little cars; not because any of my friends have RX-8's (ok, one friend has one, but I didn't know it when I bought mine.) But who's to say why I like fast, black, sports cars? I look at it more as a matter of accretion, over the course of decades, and the influence of many sources... not something I can pin on any specific (small) set of immediate influencers.<p>Clothes? Hmmm.. I don't dress like anybody I know, since I like to wear waist-coats and cravats with jeans. It's an eclectic taste I glommed together from bits & pieces of various influences.... being a Doctor Who fan, liking the Steampunk genre, Victorian era fiction, etc.<p>Now is any of that <i>purely</i> rational? Hell no. There's definitely a peer influence, "glommed together from bits over time" aesthetic. But there is (sometimes) a rational aspect mixed in. Like choosing a certain music player because of it's format support and storage capacity, or choosing Mazda because they have a good quality reputation, etc.<p>I guess that was a lot of words to say "I don't know," but that's kinda it. It's hard to isolate the different factors that go into these decisions.