Friday is a weekday, so I treat it like a weekday. I do my work on a Friday rather than getting all excited over the weekend because I know that if I don't do things on Friday, they'll just roll over to Saturday and Sunday anyway.
That said, sometimes I do deliberately leave work for the weekend - during the week I'm a really busy guy and on weekends I've got very little to do in comparison, so I get bored of them fast. Shifting some work to the weekends gives me something to do during the day and also helps ease up my busy weeks. So thinking about it, I guess I don't look forward to the weekends because I've got less work to do or whatever; I actually tend to make work for myself on them. I hate sitting around doing nothing, which is something I'd be doing more of than I'm comfortable with if I didn't have work for the weekends (not that, with the amount of work I get to do, I'd have the weekends off anyway - but still!).