Proprietary OCR ( Optical Character Recognition ) software from ABBYY, Expervision, OmniPage, PrimeOCR, Readiris, SimpleOCR etc are expensive and resource hogging. The Google Docs online will support OCR, currently available as a demonstration only. Use the demonstration page for now to test the OCR service. You’ll find many errors with character recognition, but the service is free and it’s constantly improving until it is completely integrated into Google docs.
ABBYY FineReader Online is one of the best online OCR services with free version limited to 10 pages a day.