Internet Searching Using Regular Expressions?

/[Aa]non([aiy]mo?u?s)? [KkCc]ow[ae]rd/ asks: "Remarkably few people have a working understanding of regular expressions. But, those that do know how useful they can be for searching text. Has anyone out there seen a large search engine (like Google) that will take regular expressions for queries? How about a newsgroup search engine?" Aside from the fact that many regular expressions read like snippets of line noise, they are the best thing I've seen for searches, and it's a lot easier than -adding +alot +of +search -terms.