Any alternative client that can be used to solo mine yet ?
If you solo mine, you will get less bitcoins than what you would theoretically get via mining in a pool, because the block variance for a small hash-rate is larger than the amount of time for the difficulty to increase.
I know this already !
I was asking if there is any alternative client that allows me to solo mine ... but I guess only the original Satoshi client provides workers with getwork things for solo mining short of a private poolserver on the LAN.
Probably you can solo (or p2pool) mining with this:
Libcoin: https://github.com/ceptacle/libcoin/wiki
Announcement: http://www.mail-archive.com/[email protected]/msg00762.html
Best!
Thiago
Go Bitcoin! 
