Well, there's always the Macbook Pro line, favorite among designers, editors, hipsters. I'm yet to be convinced that one needs to overpay for a design computer, but to each his own. You can actually get some decent used MBPs that are 3-5 years old that should still be powerful enough to run design programs, but you have to be be careful and picky when buying used...
As far as PC, pretty much any laptop line will work, I highly suggest that you spend the extra money on a business line, regardless of manufacturer, as they usually put higher quality hardware in those, so technically should last you longer. If you're buying new, I also do not recommend that you try to save money and get cheapo models, youll pay for it in computer repair. I personally prefer Lenovo and HP, but really as long as you're getting a business line computer, it doesnt matter who the manufacturer is. I know that Toshiba used to have horrible overheating issues, perhaps they've resolved it by now.
If you've got the money, I suggest you install a SSD drive to use as your work/scratch drive as it will help files load faster. And for storage just use an external HD. As far as computing power, you'll want nothing less than a Dual Core, at least 1.5Ghz, and as much RAM as the laptop will fit. I'm not a designer, but I do fiddle around in PS, and I find that my Lenovo W510 (with Intel i7 1.6 Ghz, 12GB RAM) is plenty fast for what I do. Try to stay away from AMD chips, as they tend to have more overheating issues than Intel chips.