PrimeGrid now supports Linux sieving as well as Windows 32 bit and Windows 64 bit.
Code:
PSP Sieve 
Platform Current version Installed 
Microsoft Windows (98 or later) running on an Intel x86-compatible CPU 1.02 13 Oct 2007 12:21:18 UTC 
Microsoft Windows running on an AMD x86_64 or Intel EM64T CPU 1.02 13 Oct 2007 10:49:17 UTC 
Linux running on an Intel x86-compatible CPU 1.02 31 Oct 2007 10:14:27 UTC