PC programs on a Mac?
No.

And yes.
If you slow down your Mac by running a PC emulator and Windows on it, and it has the newer Intel processors (Macs have gone mainstream at last) then probably.

But why buy a Mac and then run Windows on it?
Why not buy a decent PC?

What's held me back from going Mac is the loss of most of the applications I use and the cost of buying either Mac versions or native Mac replacements.
The only one I know I can use is Lightroom, which comes in PC and Mac on the same disc.

Then there's the (in)compatability between Mac and PC when sharing files and disks.
When we had Macs in Germany and I was supporting older Mac applications (my experience is 4 yeas old) the biggest problem was the Mac apps would use weird characters in file and folder names that the PCs just could not cope with.
Like bullet points - yeah it looks pretty in finder, but it's not compatible!
Applications like MS Office on the Mac were so far out of date as to make it incompatible with the rest of the company, nowadays you can probably get by with Open Office for most work. Only users of Office 2007 on PCs will give you trouble.

I've been offered a Mac laptop, so if that materialises (may be a Xmas present) then I can give you my blow by blow account of conversion, and interoperability with the house LAN and the PCs.