The one I use the most is a MacBook Alu, but on my desk at work is a Mac Pro, which I also use a lot. Tend to do most of my email, browsing, writing on the MacBook and design work, testing, gaming and more on the Mac Pro.
My main computer is a 20 inch Intel iMac (the white one), but my main laptop is a beat up iBook G4 from 2004. I also get a lot of use out of a recently acquired PowerBook 3400c (my Newton/QuickTake machine), and my main writing computer is (no, this isn’t a typo) a PowerBook 145B. I also have a PowerBook 1400cs, two PowerBook 5300s (everyone hates them but they are great computers), a Newton 2100 and 120, a QuickTake 150 and several other old Apple devices. I might have a problem…
I’m still in the PowerPC guild, since my main machine is a 12-inch DVI PowerBook G4 (1GHz, 1.25 GB RAM). It’s really a compact powerhorse. I’ll probably get a new MacBook in the next three months, but I’ll never leave the PowerBook behind; I’m planning to buy a new battery and AC adapter for it, and a bigger hard drive as well.
Other Macs I use on a daily basis are a PowerMac G4 Cube, a TiBook and a clamshell G3 466MHz graphite iBook :)
My main Mac is a MacBook 2.2GHz with 4GB RAM and 80GB disk. This is a great machine for everything because it runs Windows and Linux in a virtual machine so I can do all of my work on one machine. The only thing I would change is that I need a bigger internal hard disk. This replaces a G4 PowerBook that I sold when I bought the MacBook.
My other Mac is a 733MHz G4 PowerMac so I can test my software on a PowerPC on OS X 10.3. I paid $150 for it used but absolutely like new and it even came with the original installation disks. Sweet! :-)
Also have a Mac XL (Lisa) but I seldom turn it on anymore, and buried in a box someplace I have a Mac Plus.