How about the Asus M6N 'whitebook'? It has all those options available and weighs around 6lbs. Where I got mine those specs (though I'm not sure about the HD cache) plus a B+G Centrino internal WLAN and standard DVD/CDRW would run ya $2014. That's with no OS though, but it comes with carry case and model-specific driver CD- I bought mine w/o OS, installed w2kpro myself, and luv it to death.
Also, the gfx GPU is a 'plain' radeon 9600, which Asus underclocks by default, presumably to extend battery life. It's extremely easy to juice up with ATItool though, and some other owners have gotten 11k+ scores with it overclocked in 3dmark01.
Have a look: http://www.rjtech.com/miva/merchant.mv?Screen=PROD&Product_Code=A-M6N&Category_Code=ASUSN