In 1997, McNealy banned the use of Powerpoint at Sun because it clogged disks, bandwidth and brains:
We had 12.9 gigabytes of Powerpoint slides in storage on our disk drives. Ha ha ha. It freaks me out just to think about. Do you how many person centuries that is? Of clip-art manipulations? I banned Powerpoint from our company - I just edicted it. [...] if I just gave everybody overheads, you know, blank Mila overheads with all the free pens they wanted - I could drive productivity through the roof, as opposed to having - I mean you've all seen these overheads that have 14 pieces of clipart, 13 fonts, right hand justified, spell-check, 13 colours and you know your employee is exhausted by the time it finally comes off the printer. And do they communicate anything? No.
McNealy hand-draws his overhead projections (source: somewhere in Infodesign Cafe's archives perhaps).
More how we work.