Fans of Resident Evil Outbreak, a spin-off series for PlayStation 2 released about 10 years ago, have managed to restore online play for the game on a private server, though only for its Japanese versions.
Outbreak Server came online recently for both Resident Evil Outbreak and Resident Evil Outbreak: File #2. The project reverse-engineered the server with packet captures from the NTSC/J versions of the game (according to this FAQ) but no such captures for American and European versions have been found so far. "We hope that we will be ble to create servers that will work with the NTSC/U and PAL versions of the game," the creators wrote in the FAQ, but absent those, NTSC/J is where the action is for now.
And no, they're not doling out download links for the game, either. "We will not tolerate piracy discussion here. Nor is there an excuse not to purchase a legitimate copy," they say. The project is a server to host the game's multiplayer only, it doesn't touch the game's assets otherwise.
Resident Evil Outbreak and Resident Evil Outbreak: File #2 had a dedicated following that had been agitating for Capcom to revive the series, either with a sequel or in re-releases. For now, this is as good as it gets for them.