Final Cut HD Pro (pro video editing), iLife (seamlessly integrated consumer media production and management, free with every Mac), Xgrid (instant, easily-managed clusters), Logic Pro (pro audio creation), Xsan (ultra-cheap SAN creation and management), Remote Desktop (haven't seen anything that good on a PC), and of course there's OS X itself.
Whoops, I think I went a bit over three, and I included titles that cater to the consumer, the pro, the scientist and the systems administrator.
Not a bad list. Let us take a look at it:
FinalCut Pro: I'd be using Adobe Premier on my Windows box. Linux folks use Kino or other packages.
Xgrid: This is a server product, in which case I'd be going with either Microsoft Cluster Server (Windows Server 2003 Ent. Ed.), or a Linux clustering solution if desired. This wouldn't do a thing for the typical home user.
Xsan: Another server product. I'd go with a linux box running iscsi-target, which is quite easy to set up, and I'd use the Microsoft iSCSI Initiator to connect my XP box up to it. Cost? $0 for software. Apple charges how much for Xsan? [worth note: I think Apple could be a leader in the enterprise hardware market, but they're more interested in selling iPods instead of selling their rackmount servers and RAID arrays, which appear to be excellent products]
Remote Desktop: What? You can do that with a Windows server, or an XP client. For free. Or I could go with the classic VNC, again for free. Pff, I can even use a Linux workstation to remote back to my Windows XP or server box.
OS X itself: I'd dare to say that NeXT, OS2 and BEoS serve as testimonies to the fact that an OS without software is a doomed OS. OS X without worthwhile software is just eye candy. OS X might look nice, and it might be a pretty nice rebundle of BSD, but without the software, it's pointless. And if by "software" you mean Linux titles, I'd wonder why bother with OS X in the first place? Just run Ubuntu or any other Linux flavor on a basic Windows box and save loads of cash.
My position is this: Apple sells overpriced consumer PC hardware and a markets it to the AOL crowd. They hype the ability to run Windows software, in effect, admitting that the software users want to run is Windows software. In my opinion, folks would just be better off buying a much more inexpensive Windows PC in the first place. Folks are entitled to buy what they want, and if they want to pay too much, they're welcome to do so.