I had a desktop computer for at least 8 years then last aug finally bought a laptop computer for the following reasons-
laptop is mobile so i can use it in any rooms.
A lot less wires/cords for my 4 mischievous cats to unplug!
I can close the laptop on top of keyboard so the cats can't play with the keyboard.
I wouldn't have to look all over for my mouse (cats would knock it off the desk so it'd be behind the desk, etc.
After having it for a while and LOVING it, something happened that made me VOW to NEVER NEVER BUY ANOTHER DESKTOP COMPUTER!
In Sept, there was a big hurricane hitting my area (MD/DC/VA/NC) and my paranoid sister in Utah would page me every half hour to get online so she could be assured that I was still alive and kicking. After 5-6 hours of this, I lost all electricity so I thought "now my sister will freak out because I won't be able to get online and let her know.." then she paged me to get online and I thought, "well, let's see if I can do it with no electricity" and to my surprise, the laptop functioned fine. I forgot that the laptop has its own battery (about 4 hours worth) so I was able to communicate (SHORT CHATS) with my family via internet for the next 5 days until electricity came back on. Therefore, my family didn't go insane worrying about me.
SO, laptops are very good for emergencies also.