I currently run a fleet of four Macs, because I kinda hate getting rid of things that are still working.
- Powerbook G3 Pismo, 500MHz, 512MB RAM, 32GB HDD, dead battery and non-functional optical drive. Has Mac OS 9.2.2, 10.2.8 and 10.4.11 Server installed. Can also boot 10.1.5 and 10.3.9 from an external FW400 drive. I use it mainly to run pre-OS X games and apps and also for development and testing, as it can run every OS X version up to 10.4.11.
- Powerbook G4 12" 1.25GHz, 512MB RAM, 80GB HDD, also has a dead battery. Runs 10.4.11 and can also boot 10.5.8 from the same FW HDD as the Pismo. It has a mix of OS X and Classic games and hasn't seen much use lately. It has both Sheepshaver and Basilisk installed, but my experience with it hasn't been good, it crashes a lot.
- Mac mini (mid-2007), Core 2 Duo 1.83GHz, 1 GB RAM, 80GB HDD, dead optical drive. Runs 10.6.6, but I intend to fix its optical drive, get a large HDD, increase the RAM and repurpose it as a media center/file server, probably rolling back to 10.4.11 Server. I currently only turn it on to sync my iPod.
- MacBook Pro 13" Core 2 Duo 2.4 GHz, 4GB RAM, 250GB HDD. Runs 10.6.6. It's my main machine, but I don't run many Garden apps on it because the Powerbooks are better suited to the task.