Metro Architectures Enabling Sub-Wavelengths is a project that directly addresses the central theme of the 4th Call for Pervasive & Trustworthy Network & Service Infrastructure. This central theme is the recognition worldwide that the network architectures of the last 20 years were never designed to cope with the new types of demands driven by phenomenon like the Internet, Video, Search, Social Networking and Cloud Computing. MAINS proposes 2 new architectures, a new approach to network management and will demonstrate an application that uses this new architecture to virtualise personal computer services. The key is the use of sub-wavelengths (bursty time-shared use of a single wavelength) by building an architecture based on dynamic time-shared use of ultra-fast tunable components and optical burst switching systems. Furthermore, the MAINS project will evaluate its outcome in hybrid mesh-ring test-bed that features innovative sub-wavelength switching nodes from University of Essex and Intune Networks. Finally, MAINS will perform a field trial involving real users in Cyprus, which will demonstrate a virtual PC application over sub-wavelength switching network as a proof-of-concept. MAINS outcome will allow efficient deployment of distributed application servers in a metro network, by means of a novel service to network interface and an extended GMPLS control plane. As a result, both CAPEX and OPEX are reduced, while enhanced capabilities for service deployment are achieved.