Hi All,
Recently I picked up some cheap PSOne Books releases (Gokujo Parodius Da & Detana Twinbee Yahho) and decided to whip up some spine labels for standard sized jewel cases.
PSOne books was a re-release series (think greatest hits, but cheaper) in Japan that continued well into the later years of the PS2; they sold new for as low as Y1500 up to Y2500 for multi-disc releases. These days you see many of them at used book stores for like Y500, and they tend to be pretty cheap even from importers on eBay. The problem is that they shiped in slim jewel cases, with a full-color manual, cover card, and a spine card (which is almost always missing from second hand copies).
Here's an example of a complete copy of Rockman 6 Complete Works;

Anyhow, I snagged a couple of Konami Cute-Em-Ups on the cheap recently and decided to re-case them in standard jewel cases, so I whipped up a quick and dirty spine card replacement. It's not identical to the release version, instead it's a mashup of the front and back spine-card content;

The barcode is in the correct EAN-13 format used by Japanese retailers, and is scannable. I used this generator to make it;
http://www.free-barcode-generator.net/ean-13/ (Code Scale 300%, Code height 50%)
The flavor text might not be correct, as it was generated by using the Google Translate App to OCR the back of the manual. The text was then put into an HTML document with right to left vertical formatting (I don't think Gimp can do this) screen grabbed from a browser, and pasted in.
Anyhow this is how it ended up looking in a standard Jewel Case (sorry for potato quality);

I contemplated doing a full back-cover, but in the end I'm really happy with how this turned out. It matches the aesthetics of the PSOne books release, and doesn't require hunting down high quality scans of the original Japanese back-panels. If you guys are interested I can post the Gimp template for this.