Darkstalkers Chronicle: The Chaos Towers – Sale (now $4.99, original price $9.99) Fate/unlimited codes – Sale (now $9.99, original price $19.99) Power Stone Collection – Sale (now $4.99, original price $9.99) Ultimate Ghosts 'N Goblins – Sale (now $4.99, original price $9.99)
PSP minis (also available from PS3 Storefront)
minis (PS3 and PSP) Cohort Chess (£1.99/€2.49)
PSone Classics (PS3 and PSP) Gex: Deep Cover Gecko (£7.99/€9.99)
I'm pretty sure you can play imported games on a Saturn without having to make any physical modifications to the console, so if you're wanting the disk purely for the purpose of being able to play the game again, there are probably other alternatives.