0NL1NE is the name of a system that uses the Digital Monster Communications system created by BladeSabre at the WithTheWill forum to allow the Digimon Virtual Pets (and some Digivices) to communicate over the internet.

0NL1NE works through turning your digimon's information into a copy of that digimon in the form codes called "Digital Read-Only-Memory" or DigiROM, for short. These DigiROM are extracted using the D-Com, sent back and forth between Tamers, via instant messaging systems and any other form of online communication, and then inserted into the device to fight the digimon that has been received. This is explained further in the Guide.