I tried Sh3 on my laptop
IBM T42
1,8Ghz Centrino
1 Gb ram
ATI 64 Mb card
Worked OK. Choppy during explosions and when the periscope came out of the water.
Im gonna upgrade my gaming at home to
AMD 64 3200+(2.0Ghz) OCed to 2,7 Ghz!

ATi X850 XT PE 256 Mb
Yummi!!