dude...I wouldnt get a macbook if you paid me, the best bang-for-your-buck is easily an iMac, and they're pretty portable these days. Any gig I've ever had (djing at friends parties - not really a gig as such but anyways) I've had to lug other stuff around anyways, so the extra size of the iMac is irrelevant to most people - in my opinion. Its a bit of a electronic-music myth that you should get a laptop, again - just one of my theories.
I see so many people with laptops, paying through the nose for its portability and not really using the type of portability it excels at. Still using it like a desktop at home, and still carrying loads of other things to gigs with them like mixers & amps etc etc..... so they pay more, for a lesser spec'd machine, cos thats what musicians are supposed to do - get a laptop.
you could get a super pimped out iMac instead. massive screen, wireless keyboard & mouse...no horse-shit problems that seem to plague laptops, REV A mac laptops especially (or should I say notebooks cos apparently there not designed to be put on your lap any more - too hot)
and one of these for when you're gigging or going to someones house to jam
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