Sandstorm is worth trying as a replacement for an organisation's cloud software.
Good things: Makes a wide range of open source web-based collaboration and business tools easy to install. One shared login system simplifies adminstration. Control your own data.
Bad things: Concept of grains is confusing in the user interface, users may need it explaining. Often feels alpha quality.
Future promise: Good community constantly adding to the ecosystem of apps which can be installed. Core team solving the tough engineering challenges.