1up has an interesting article right now about how dedicated homebrew guys put together, test, and actually manufacture modern-retro cartridge games like Retro City Rampage. Sure, you could just emulate, or get a flash cartridge, but let’s be honest: there’s nothing like the real thing. Even if it isn’t real.
This is sheer speculation, but I’m thinking that having a complete retro-style box, rental-style plastic case, and old-school-mom-and-pop-style fabricated receipt is going to pretty much make Retro City Rampage the must-have swag stop at PAX. The game looks pretty awesome, too.