depending on how "make or break" you are about your wallet, laptops are the one purchase that can do both. Only thing is, if you want good, you will definately get the "break" part. I recently purchased a new Dell Inspiron 5150, and tweaked the crap out of it with upgrades. It started around $1400 I believe and when I was done with it it ran me almost $3k. Granted, it will play nearly every game out there and even most heavy 3d applications (which are both important to my business), so I cant complain. I am very pleased with my laptop and I have not complained yet. Check out Dell and pick a base laptop, then modify hardware from their "personalising" option.

Needless to say, it is VERY important to know exactly what you will be using it for before you buy, cause upgrading a notebook isnt exactly 100% possible for all hardware.