Preferred hardware

This is only a short list of the hardware and vendors I most often find myself buying

Servers

Since I don't have a proper server room I use PC sized cabinets with standard motherboards.
A new server for my purposes would typically be based on the following:

Asus motherboard - since I own a cuple of K8V-X and similar priced
Amd64 CPU - typically not the latest greatest, but a more cheap around 2GHz
Memory which can be Kingston, Corsair, hmmm dont have any bad experience last couple of years
Hard disc drives I use software RAID so I always buy two discs for the OS, most of my 3,5" discs are Maxtor, but for laptops I have used Fujitsu discs
Should I need more Ethernet ports I usually buy some Intel PRO network cards

The reason for using the above is mainly that I use these servers for OpenBSD and support for Amd64 is superior and gives an added security with non-executable bits etc.

Laptops

I almost exclusively use Mac OS X for workstations and thus I buy Apple laptops for workstations. They come in a nice box and are easy to get installed within a few hours. Whenever I am in need of another laptop for Windows or OpenBSD/i386 I buy Lenovo Thinkpads.

Dont buy anything else.

Printers

I dont buy printers a lot - but when I need to choose a printer these things are important to me.

built-in Ethernet network is a must
postscript is nice, brotherscript is fine, PCL is OK - Windows only printers - fuck off
laser is a must, I might use other technologies, but NEVER EVER will I buy a printer using ink again

So I bought this Brother HL-2600CN in 2003 and it worked perfectly - but have some problems now :-(.
When I needed a printer for home I bought the Brother HL-2700CN which is an A4 color laser printer with built-in network card, BR-Script3 and I could easily upgrade the memory myself.
I can recommend the color laser printers from Brother and I expect this printer to live for at least 10-15 years.