You can never have too many options when interfacing with older devices that may have originally been past their "use by" date. One example of this is by Arduino forum member "sentrygun53" who has published an Arduino sketch to print text to an older printer with a Centronics parallel interface. For the younger readers, look for a printer with a socket that accepts a plug like this:
The author has successfully tested the sketch with a HP Deskjet inkjet printer, and with some experimenting should be fine with others. There is also some further discussion about using port manipulation and interfacing with other parallel devices such as flatbed scanner mechanisms. Click here for more information and discussion. And for more, we're on twitter and Google+, so follow us for news and product updates as well.
If this type of project is of interest, you will enjoy the book "Practical Arduino" by Jonathan Oxer and Hugh Blemings:
Using this book you can create your own Arduino-based designs, gain an in-depth knowledge of the architecture of Arduino, and learn the easy-to-use Arduino language all in the context of practical projects that you can build yourself at home. Get hands-on experience using a variety of projects and recipes for everything from home automation to test equipment. For more information and to order, click here.