quarkcoin -
http://www.qrk.cc/I got lucky and mined one within a few hours of setting up client on my i7 thinkpad, but haven't mined one since (less than a week, don't run all the time - heat not good for laptops)
It pays out 1 QRK for every block - currently just over 1 cent USD but I think it will go up.
blocks are written about every 30 seconds.
Quarkcoin is coming up on its 1 year anniversary.