Wow this one turned into a flame fest fast.
UPS does deliver on Saturday, for an extra $30 a package. They have done that since the day the company started. They didn't used to charge extra for it though when they thought they had to actually compete with the USPS.
Fed-EX is by far the superior shipping company though, in my opinion, mostly due to customer service and better shipping options and times.
And for the guy who said UPS takes 2 weeks to deliver a package.... WTF are you talking about. I worked for UPS for almost 2 years in college and it never takes two weeks to deliver a package. Maybe something international, but still that doesn't even take two weeks! If one time in your entire life a package took a few days longer due to a holiday rush or bad address info, or anything, that doesn't mean the company sucks and you don't need to exxagerate the timeframes.