I'm working with a couple partners and programmers to develop a black box. We'd like to find the best way to plug into a market feed so we can test our product in a live market environment. Ideally, we'd like to plug directly into INET using their ITCH datafeed. Unfortunately, it seems they only offer this service to broker-dealer members of theirs. Is there another service out there that offers plugging into ITCH? If not ITCH, how about any feeds using FIX? Any help is appreciated. If you've had experience doing the same and would like to offer other suggestions too, that'd be great. Thanks.