Smile on My Mac just released version 4.0 of PDF Pen. Perhaps the most needed of the new features is the capability to OCR, something sorely missing from Leopard’s built in Preview application. Other features include the ability to sign documents and apply stamps. Right now Smile on My Mac is offering PDF Pen 4.0 at a 20% discount off the regular $49.95 price. If anyone has experience with the OCR component, let us know in the comments.