Non Java options?

Lucene and Nutch may sound good if you're familiar with Java, but what if you're not? Since drupal is written in php, are there any php crawlers that drupal might integrate well with? I've tried phpdig but found it to be slow and not well supported.

I've also found rdig, a ruby module but it doesn't seem to have much documentation or support. I'd love to hear other people's opinions on this.