Can SimplePie grab data from any element in the feed?

Beginning with SimplePie 1.0, you can now dig through SimplePie's internal data array to parse out data that isn't formally supported by SimplePie's public API methods. The methods designed for this are get_channel_tags(), get_feed_tags(), get_image_tags(), and get_item_tags().

This tutorial shows an example of how to grab custom data from a feed.