Distributed Proofreaders
Help bring public domain literature into the digital world by joining the Distributed Proofreaders (a sub-project of Project Gutenberg). As a proofreader, you compare scans of pages and the corresponding text to fix the errors made by the OCR software. Not exactly thrilling work, but perhaps a more productive hobby than Weboggle. The DPs have just completed work on their 5000th book. And I've contributed 4 pages.