I personally recommend MSi ... completely linux-ready out-of-the-box, and pretty cheap too. I have the MSi A6200...
Intel Core i5-430M processor
4GB DDR3 RAM
Intel GMA HD Graphics (plays games pretty well, although I'm not a super hardcore gamer, I mainly use it for media ... works perfectly fine playing on 1080p 50" TV)
15.6" HD 1366x768 screen
Atheros AR9285 b/g/n wireless card
Realtek RTL8101E/RTL8102E ethernet card
3 USB 2.0 ports
1 HDMI port
1 VGA port
SD/xD/etc. memory slot
Aesthetics = layout is a clean and sleek black, with subtle diagonal stripes
Keyboard = very responsive chiclet keyboard, with full 10-key setup
Internal mic/webcam = pretty standard on modern laptops, but still worth mentioning
As I mentioned, everything worked completely fine out-of-the-box for LMDE, as well as LM 10/11 (back when I believed in Ubuntu). My cost at Office Depot (and I paid full retail) was $485. That is USD, which I only specify because you mention euro. I know you were originally looking for mobile broadband, but quite honestly with the money that you save, you can probably afford any card to slide in. That is, assuming you can't tether your phone's internet through USB (my version of mobile broadband).
the beauty of linux is that the rabbit hole goes as deep as you want it to go.