Ability to enter a Challenge Grant - essentially a Matching Gift from an individual. Donor A (individual) agrees to a pledge amount A$ if other donors contribute their own gifts against the pledge. Once the total pledge amount A$ is reached, be able to "call in" or Invoice / record Donor A's contribution matching targetted amount. Would also like the flexibility to have Donor A give the total amount up front as a challenge grant, but have other donors contribute "against" the challenge gift.