Spigit brands itself as a purpose-built social networking tool for the enterprise, but it’s more than that. It’s a fully customizable engine for idea and innovation management. Since we first noticed it in 2007, it’s grown to be the solution of choice for 15% of the Fortune 500, and added a unique set of features that have led to InnovationSpigit 2.0.

Through a SaaS web application, Spigit adds social and algorithmic filtering to let companies develop a granular process for developing new concepts, and lets managers of that process see detailed metrics on the state of an idea. InnovationSpigit 2.0 adds a richer virtual incentive system to the mix, one that draws everyone in the enterprise into managing innovation.

Rather than using a generalized app and soft social networks to nurture new concepts, which can quickly become chaos in environments with thousands of participants, Spigit uses a virtual currency system of reward, an algorithmic reputation system for users, and Digg-like voting on individual proposals to strictly organize information.

It’s the application of game theory to a virtual currency system that really differentiates Spigit from other innovation management solutions, like BrainBank, Brightidea, and Imaginatik. While at first users might find it strange to be pushing an idea towards acceptance with virtual stock purchases, they’re likely to find it less so when they discover they could potentially buy real world rewards and swag with the returns.

If there’s one criticism to be made of Spigit, it’s that the product is so feature-rich that it’s not well suited to the small enterprise. Both the price point and the power of Spigit are probably overkill for anyone but those with extremely large overhead when it comes to information management.

But the good news for those who do have that kind of overhead (like if you’re Pfizer) is that Spigit offers a pretty robust solution for managing the flow of ideas that makes the enterprise tick.