The 'official' HNSearch is completely useless for anyone who would ever want to search HN. It's a Firefox Extension (!) that adds a 400px sidebar to your google search results pages showing site: searches along with an extra adsense ad. It's less useless than the 5 IE toolbars your annoying relatives live with, but just as obnoxious.

I just installed it again for a laugh, and it actually redirects to searchyc.com results when you click on its "Hacker News" header — even though pg staunchly refuses to ever link to searchyc. I made fun of him for it at his party before Startup School and he tried to laugh it off with "they're a YC company!" as if that weren't obvious on the face of it.