Infinitecoin is a Litecoin fork and uses the scrypt Proof-of-Work hashing algorithm. It has a 30-second block target and the difficulty retargets every hour. There is a total of 90.6 billion Infinitecoin. Block rewards are 524,288 Infinitecoin per block and halves every 86,400 blocks (roughly 1 month). Infinitecoin was launched on 5 June 2013.
Gapcoin is a new prime number based p2p cryptocurrency, which tries to eliminate the sticking points of other scientific currencies like Primecoin or Riecoin. It's a fork of Satoshi Nakamotos Bitcoin, a decentralized payment system which is independent of banks, governments and other centralized regulators. With Gapcoin, you will be able to anonymously send money around the globe in no time. The big improvement in comparison to Bitcoin is that instead of burning electricity for its own sake, Gapcoins Proof of Work function actually does useful work by searching for large prime gaps