RIFT soul calculator.
The tool allows rifters to experiment with builds all the way up to the game's level 50 cap (even though RIFT's current beta phase doesn't allow for endgame play). ZAM's announcement post carries a beta qualifier of its own, as the soul calculator is still under development and may feature a lingering bug or two.
RIFT is a subscription-based fantasy MMO developed by Trion Worlds which launches on March 1st. You can learn more about the game and sign up for beta via the official website.