I have on occasion, but purely as a "gee whiz" kind of thing. Some sites, like iPorn, seem to cater to this format. I'm a member of several of the bigger sites and almost all have a dedicated "iPod/iPhone" format so it must be getting pretty popular. At yesterday's big Apple event, they revealed that there are now over 40,000,000 iPod/iPhone's out there so it sounds like a very strong media player category overall.

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