The youtube search does a good job of searching videos. In its search page, it allows you to search by popularity/ratings/date. I have found that videos with longer playing time are usually the ones I am interested in, however, there is no option to sort the results by playing time.
I did a bit of digging in the Youtube Developer's guide and saw that they give the length of the video in seconds. The next piece was Yahoo! Pipes. I created a pipe which would fetch videos from youtube and then passes the results through the sort operator to sort the results based on the yt:duration field. Tada! That gives me videos matching my search criteria near the top.
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