This shall become a list of Bitcoin derived alternative cryptographic currencies that came up with technical innovation. Coins on the list must have been publicly launched. Claims must be verifiable at least by looking at the code. In order of appearance.


Namecoin - NMC - thread
Decentralized name/value storage to be used for DNS, TLS, IDs, Login, Filesig, etc.
Bitcoin merged mining (implemented 2011-06).

Devcoin - DVC - thread
90% of generation goes to cryptocoin developers.

Ixcoin - IXC - thread
Small parameter changes.

SolidCoin - SC - thread
Faster blocks.

Tenebrix - TBX - thread - dead
New hash algorithm (Scrypt).

Freicoin - FRC -thread
Demurrage.

PPCoin - PPC - thread
Proof of Stake (combined with POW)

Junkcoin - JKC - thread
Fancy reward amounts (Special starting rewards / Random rewards).

Florincoin - FLO - thread
Transaction comments.

Primecoin - XPM - thread
Hash algorithm looks for special chains of prime numbers.

Quark - QRK - thread
Multiple hashing algorithms.

MemoryCoin - MC? - thread
Grant awards & grant voting system

HunterCoin - HUC - thread
Human Mine-able CryptoCurrency Game (Pretest for "Chronokings")


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Floating difficulty retargeting.


Thanks to everybody helping compile the list (see below).

You are more than welcome to suggest changes/corrections or new entries (in proper format).