MDD G4 PowerMac and a Powerbook G4. I can't afford to upgrade to a Mac Pro so I got a Windows 7/i7 machine to split time on. I still wish Apple would build a mid-tower, but until I can afford Macs again the Windows PC will have to do.
Also, I'm waiting for eBay copies of Leopard come down. I'm not paying $129 after I've already spent so much to upgrade these things. My only problem is that probably in a another year or so most current web browsers probably aren't going to be that usable and there will be no PPC upgrade path. The thing that annoys me is that the all of the iPhone and iPad processors are RISC which means Apple still has to develop a growing chunk of OS X for RISC processors, so Apple could still be developing future versions of OS X on PPC machines with very little in development resources, but they choose not to in an effort to coerce users into buying new hardware. Maintaining PPC code for OS X would be far greener than being passive aggressive about telling people to buy new Macs.