There's an On-U promo CD called "30 Years Of Excellence In Sound" currently doing the rounds, put out by Domino, who do On-U's publishing - there's one on eBay - it's a tad expensive, but the completists will want one, I'd imagine...
Here's a couple of pictures which I lifted off the eBay listing - they're a bit on the small side though (you can zoom in on the pictures in the listing)
It does feature the instrumental mix of Little Axe's "Song To Sing" which I think was only available to download from somewhere (memory's a bit foggy on this one), plus the Peaking Lights remix that AMS did
Finally, here's a bit from the Domino blog that mentions it: