GAPCOIN

The largest, decentralized prime gap search

Website: gapcoin.org
Twitter: Gapcoin

Specifications:

PoW: custom, prime gaps
Block target time 2.5 minutes
Block reward proportional to the current difficulty
Block reward halving every 420000 (about 2 years)
Cap: about 10 - 30 million GAP
Difficulty adjusts every block and increases logarithmic (it will probably take years to get to 50)

Fair launch:

Gapcoin was not designed to enrich the early adopters or the coin creators! The more people mine Gapcoin, the more coins per block will be produced. (Coin supply will increase logarithmic with the difficulty, this means it will grow in the beginning, but later, it won't change much.)
There won't be any premine!
To avoid instamine, the reward of the first 1152 blocks (about 48 hours) will increase quadratically to its absolute value: the current difficulty. Block reward will be 1/1152^2 * blockheight^2 * difficulty for the first 1152 blocks. This should guarantee that the difficulty is stable until the blocks yield a worthwhile amount of coins.
Source code will be available before launch (excluding the PoW function), so everyone can setup their own environment, compile the software, and check if everything works.
Windows and Linux binaries will be distributed in an encrypted container before launch, the password will be revealed at launch.

Launch date: Tue Oct 21 2014 - 18:00 UTC

Edit: Website now contains a mailing list.
Edit: Reward scheme changed: Block reward halving every 420000 (about 2 years) with about 10 - 30 million GAP.
Edit: We have an new and unique logo.
Edit: Launch date released

Launch thread: https://bitcointalk.org/index.php?topic=822498