Quote Originally Posted by OErjan
the thinkpads from IBM tend to work well, and ACER has travelmates andaspires that also work OK.
Actually only things i find working less than optimum (any make) are built in modems and wireless. otherwise things tend to be fairly straightforward.
I would argue that even notebooks with built-in wireless are perfect candidates for installing Knoppix Linux. I don't use a modem anymore, so I can't tell you about the built-in modem compatibility of Knoppix with laptops, but built-in wireless is pretty well supported in my experience. Here's an idea for you:

When you're going to check out the laptops, bring a copy of knoppix and a thumb drive with you.
When you get there, ask the salesperson if you can use their Internet connection to download the manufacturer's driver files for the built-in wireless card. Once you download the driver file (likely a self-extracting EXE) you will have to extract and save the *.inf and *.sys files for that card to your thumb drive. Boot Knoppix on their demo model and use ndiswrapper to grab the driver files off the thumb drive and get the card up and running. If it doesn't work, check to make sure the wireless card's switch is flipped "on," search Google for the correct file to use with that card and ndiswrapper. If you don't find anything, try another model.

Having built-in wireless on my laptop has been the best thing about owning it. Linux is a powerful OS, and it's really fun to play with, but without an internet connection, it's a lot less fun.