Well I guess that depends on how you define "running"...
I'm using a P-M 1.5G CPU/Radeon Mobile 9200/1GB mem laptop, and I could play SH3.
I mean although it takes 3+ minutes to load a saved game, and whenever there is 3D object (periscope, external view etc.) it will be laggy to death
, I could still play it...
The bad thing about laptop is, you can't upgrade your video card...I hate M9200