Everybody has to do a flickr search tool in flex, so here's my humble submission. I'm still working on it so it's a little rough.
The top text input box takes flickr tags that you want to search for. If there's more than one please separate them with commas.
If you want to search for a particular user or group the next text box takes a flickr NSID, which you can obtain at http://idgettr.com.
The art / photographs section of this site is also Flex-based. It has better HTML integration than the search utility.
Both examples use the same custom Flex component which implements the two-panel selector design pattern for an image browser.
Both require version 9 of the flash player.