Again, for the Mac pricing issue.....is 26p per day really that much over the lifespan of a computer for the endless amounts of ease of use and build quality a Mac gives you.
As for the mouse, who needs one when you have a multi-touch trackpad (the size of gloucester on the newer macs). Single finger to left click, two to right click, double finger drag to scroll....and then assign what you like to 3 or 4 fingers.
As for something a PC cannot do.... Exposé on a dual head setup. My PC is dual 22" WS monitors, there are apps to attempt Exposé functions, but they seem to either be dog slow, or they use my second screen as a "buffer" to hold the windows while I choose one, creating horrible effects like windows randomly changing monitors, flickering, etc. etc. etc. Almost any Mac user will tell you that expose is a godsend.
Also, the Mac comes with a full terminal, which when you use Nano and SSH as much as I do is a godsend.
This is not to say PCs are without their benefits....I own 4 of the damn things. I like the ability to build and tweak my own kit (for waaaaay less than shop prices...I like my account manager at Dabs, he likes giving me discount). It's actually somewhat of a hobby, and really does help you learn PC hardware diagnosis (which is good for schools IT bods to know).
tl;dr version: Macs aren't that expensive if you think about it, but a PC is fine too.
