I have
1) Asus EEEPC 4G upgraded 2gbram
2) HP IntelCore2Duo 1.6ghz , 1gbram. (free from starhub)
3) Desktop PC Core2Duo 2.4ghz , 4gb ram.
My DAWs are either Cool Edit or Cubase (the one that comes with my Zoom H4s. I got 2 Zoom H4s and 1 Zoom H2, and 1 Presonus FP10. 4 audio interfaces to ensure my stability with the soundcard-backbone side.)
1) weighs 1kg, i use it to do audio cleanup.very light mixing and 2 input recording and yes it looks something like this :

optimal for boring CNY visiting when your wife is playing mahjong and there's shitload of ppl in the living room and no one in the kitchen. this was at my wife's ex company's ex colleague's house. and yeah that's the 1TB USB hdd.
2) weighs sorta more, i use it to do multitrack recording (its got a firewire port), slightly heavier duty mixing and DV video capturing.
3) i don't carry it around. there's 4 + 1 (USB hdd)terabyte of hdd in here. I use it to do video rendering + optimal audio mixing speed.
i'm done dual booting cos I need to utilize all 4 SATA slots or hard disk data storage be it video/audio/dual backup clone. so my main drive is my "abuse drive"
some ppl like Cheez will i know I used to "endorse DVD-r" back up ,but now the prices of hdd has dropped so much, (but DVD prices never dropped!) double copying on HDD is way faster and worth it.