Coiledcoin

coiledcoin was a short lived  cryptocurrency with some differences from Bitcoin:

 * Merged mining and OP_EVAL support from the start (Taken from  makomk post on Bitcointalk.com)  Coiledcoin was killed courtesy of a >51% attack by Luke Jr.   If you still want the client, I have made it available here:   http://goo.gl/wAWZN  (courtesy of tiker)
 * No legacy addresses. Anyone and anywhere that can pay to a Coiledcoin address can pay to one that requires signatures from multiple parties to spend, such as an escrow account or a business account requiring approval from two managers. It makes no difference to the sender - all addresses use OP_EVAL and look the same. (The infrastructure to spend these is fairly poor right now though.)
 * Block every 2 minutes on average, difficulty adjustment of up to 100% up/50% down every 720 blocks (nominally 24 hours), ArtForz timestamp exploit fixed.
 * 10 CLC reward per block initially, halving every 525000 blocks (nominally 2 years) until it reaches 1 CLC where it will remain forever. This is an inflationary coin, at least until you take coin loss into account.
 * Minimal 1337 50 CLC premine in the genesis block
 * Note that internally Coiledcoin addresses and transactions are formatted differently to normal Bitcoin clones. In theory you can safely use PoolServerJ for merged mining with Coiledcoin as an aux chain, just don't turn on workmaker for the Coiledcoin aux chain - it'll look like it works but the payouts will be unspendable.
 * More neat stuff (instant payments, light clients, possibly wallet protection services that require confirmation of large spends, etc) coming soon once I or someone else gets around to writing it.
 * Not sure what the initial difficulty will be yet, most likely 16