Large-Capacity media libraries supporting highly simultaneous access are more and more popular. Media libraries based on traditional client/server mode, or pure Grid or P2P can hardly meet the requirements of both high concurrency and reliable service. This paper proposes a new architecture combining Grid and P2P for media library—NeoMedia. It consists of the dedicated and volunteered nodes supported by the system server and forms a virtual media pool of large capacity. Coordinated by the system server, nodes requesting files from the media pool serve each other in the style of P2P, which further enhances the system’s performance. According to access pattern and intensity, the system server automatically adjusts the allocation of resources, adaptively optimizing the system’s overall performance. NeoMedia targets at view-after-downloading, which can efficiently utilize servers’ precious bandwidth and clients’ power. Theoretical analysis demonstrates that NeoMedia is able to support hugely simultaneous requests and provide non-trivial services at the same time with relatively low server-side bandwidth consumption.