Hiya's,
Hmm not exactly a SH tweak as such
But if you're running vista ........With Duo/Tri/Quad
Get into msconfig (start/type in msconfig or use run if you enabled it)
Goto Boot tab/Click Advanced/Check number of processors, and add your number of cores
Get's vista to boot faster, So in a way it does tweak SH as you get to play it that bit sooner
Ciao
Def