well I need a 300w inverter so i can use my electric chainsaw...
But really, i like having 300W's. If i need to I can run my computer, 15' monitor (not lcd), and with plenty to spare for all the little cool gadgets and strobe lights I have sitting around.
(no, i don't DRIVE while having the strobe lights on, or using the chainsaw, or playing semiquasylegal mp3s.)