Recently, I needed a bunch of EPS files for EAN-13 barcodes (that’s the kind of barcodes European companies put on their products).
Edit 20250520: added Wayback/Archive links but some of the below links died, so at the bottom I have added additional pages and properly archived them.
[Archive] Terry Burton wrote a great barcode writer in pure PostScript for this, with a simple [Wayback/Archive] web front end to generate a barcode one at a time.
The Wiert Corner - irregular stream of stuff 