I was trying to put Linux on my desktop computer, but it doesn't support the wireless USB dongle I use. This was last weekend. The same dongle works perfectly in Windows.
I was trying to put Linux on my work computer, but it doesn't support my three monitor, two video card display out of the box. This was about a month ago.
I love Linux, and it's fun to use on computers that have supported hardware (I love it on my ASUS netbook), but if you don't have supported hardware, it's still a nightmare.