Check out new Windows Azure Cache (preview)

Using new Windows Azure Cache, you can easily deploy dedicated, high-performance, distributed caches that you can use with your Windows Azure applications to store data in memory and dramatically improve scalability and performance. You can use a dedicated instance of the Windows Azure Cache Service for each of your apps or share a single cache across multiple apps. This latter scenario is particularly useful when you wish to partition your cloud back-end solutions into multiple deployment units; now they can all easily share and work with the same cached data.

For more information, visit the Windows Azure Cache webpage. To get started, visit the Preview Features webpage and sign up for the preview.