Heho,
i want to share some knowledge regarding a Del.icio.us Plugin with you.
Running well, you may have some suggestions for optimizing it.
Description: Searching Plugin for the Social Bookmarking Service Del.icio.us, browsing the tags, no exclusions( url’s etc.)
Problem: if you run the serach too often in a very short time, you will get an error (999) form del.icio.us, (they expacted that you are a bot), you just have to wait some minutes.