if you do not have free GPUs, you can also help with cpu using the cpu-miner from first page:
Mpos + Stratum:
http://ec2-54-198-19-83.compute-1.amazonaws.com-- connection string: sgminer.exe -o stratum+tcp://54.198.19.83:3333 -u eduffield.1 -p x
P2Pool:
http://54.200.184.132/-- connection string: sgminer.exe -o stratum+tcp://54.200.184.132:18998 -u mt2ScQSwpsohN8KC9CuFGCuCuvyJkCY8iEn1K5Y5JGe5svtfmrJ6J9McsZPJdWXPvuRq -p 1
NOMP:
http://54.183.73.24/ (Thanks Chaeplin!)
-- connection string: sgminer.exe -o stratum+tcp://54.183.73.24:3333 -u