Commercial Vacuum Cleaners

...I'm now scared of them. The other day at work, the cleaning guy (I get here in the wee hours) set this smaller version Zamboni-looking vacuum cleaner to the side while he went to plug it in. I'm walking down the hall in that direction with my jug 'o water (blah) and my breakfast lean pocket. Very nice cleaning dude plugs in the vacuum and this thing powers up and starts moving on its own! So I'm staying on the right side of the hall and it's like a Stephen King vacuum cleaner motoring down the hall....again....ON ITS OWN. So I'm thinking that surely I can get past it before it sees me...yes...I think it saw me. Well, the thing picks up speed about the time I get even with it and it T U R N S in my direction.....NO LIE...and I had to HOP out of it's way and I made kind of a...EEK sound....well it's still on the path towards me...apparently it wanted my breakfast pocket and water as well. Nice cleaning guy runs up behind me and has to put his foot out and stop it before it attacks me....which he then says....sorry about that. So from now on when I see it....I'm pretty sure it's doing that thing with the fingers and the eyes like when you're watching someone?...hey you - i'm watching you....VROOM VROOM.