What is the best laptop for a computer science student?

It all depends a bit on what you need to do with it, the OS you use and the minimum technical specifications you need.

Trying to think of all the variables:

• If you do networking and or basic programming in C or C++ or similar, a pre-war clunker with 4GB of ram, an intel celeron -20 core cpu and an embedded video card will do just fine. With Linux installed (otherwise windzozz only expols its own OS). You'll tend to need it to ssh or telnet into network devices and for some scanning like nmap, nslookup, maybe simple ping -f (flood) or little scripts in bash, perl, php and company. You can code from command line with nano or Vim (Vi for the daring ) and save CPU and ram.
• If, on the other hand, you have to do more complex things such as manage webservers, DNS, DHCP and company, assuming you run them on a virtual machine, I would say that the MINIMUM needed is 4/6GB of ram, a CPU with at least 4 cores and an embedded video card.

On the other hand, if you have to use Windows OS and software such as Visual Studio or heavy compilers, I would say that you need at least 8GB of ram, a 4/8 cores CPU and an embedded video card.

If, on the other hand, you deal with graphics and design, it all depends a little on the software you use; gimp for example is lighter than Photoshop or the Adobe package in general. But then the bottleneck could be the video card and the ram. Honestly, I don't follow the graphics part much and I wouldn't know what the minimum specifications are to do that job; also because what little I have to do, my PC can handle it just fine (CPU: Intel I7 octacore, 24GB of ram and dedicated video card with 2GB just for video).

Best laptop for computer science students

Basically a laptop with 8GB of ram, cpu, assuming Intel, I'd say a quad core I5 and in-motherborad video card with a resolution no lower than Full HD should be enough for everything.

Then again... it depends on what you need to do with it.

These conf I made with a laptop in mind, for a desktop if you do graphics buy a dedicated video card with a few gigs for the GPU (there are some great deals on high performance cards at a 'low' price); while if you do coding/networking/security any computer with at least 4GB of ram and an I5 quad core CPU is fine.

The best reasoning you can do, in my opinion, is 'aim high'.

You may never need 8GB, but having it doesn't suck and on the day you need it everything runs as it should. If it's not enough, you can always disassemble the PC and add more ram (provided the motherboard/cpu allows you to do so).

In the hope that I have clarified, and not confused more, your ideas.