Peer-To-Peer Computing is becoming a key execution environments. The potential of 100,000 of nodes interconnected to execute a single application is rather appealing, especially for Grid computing. Mimicking data P2P, one could start a computation that that no failure would ever be able to stop (and maybe nobody). However, existing models and infrastructures for P2P computing are rather disappointing: only independent worker tasks (with in general no communications between tasks), and very low level API (not even using the language-centric dot notation for master-slave communications). As a matter of fact, communicating and mobile objects provide important abstractions for the programming of such applications --- especially asynchronously communicating systems, for they allow to take into account the low coupling of P2P machines. P2P computing seems well adapted to applications with low communication/computation ratio, parallel search algorithms (Branch and X, Dynamic programming, etc.). This work proposes to create an P2P infrastructure of computational nodes and provides an API for B&B P2P applications with communications between tasks.