I feel like this concept doesn't get enough attention. You'll never get a laptop (that you actually want to carry) that has as much power as a server in a rack somewhere. Thinking of the laptop as an ephemeral mobile thin client rather than an entire workstation lets you focus on finding a laptop that's comfortable to type on and not a pain to carry. Trying to combine all of those requirements with a lot of computing power is much more difficult and expensive.

I second the earlier thinkpad X series suggestion. My x201 was less than $200, has fantastic driver support, and you can beat the snot out of them. https://www.youtube.com/results?search_query=thinkpad+x201+c...