My netbook's (Asus 1008ha) power brick says 40W output.
Dell's use a 30w power adapter.
I have a asus eee pc 1015 and according to powerTOP it uses about 10 or 11 watts while playing a youtube video, uninstalling some software, and having about 8 tabs open on chrome. The internet was via WiFi, bluetooth was off. See below:
https://docs.google.com/leaf?id=0By...MDRjMC00OWM0LThmNWEtMzYyZTAyZGY5OWVh&hl=en_GB
When its idle (still with WiFi on and the chrome open) it uses about 6.8watts