Can You Access Your Own Cash Register Data?

jeronimo989 writes "A customer of mine has a small shop and asked me to look for an electronic cash register. One of the requirements is to retrieve the sales data from the cash register in some accessible format so he can import it in the software of his choice (which happens to be OpenOffice), either by downloading the data on a Flash card, connecting a laptop via USB, or even via a direct modem connection. As far as the cash register itself is concerned, he doesn't need anything too fancy; any 'entry level' machine for small businesses is probably OK (as long as it keeps an electronic journal, of course). Which options do we have? Are there cash register manufacturers out there that allow accessing the sales data directly in an open format? Does anyone here have experience with setting up a link between a cash register and PC, preferably using free/open source solutions?"