What's your inventory count?
Let's see:
Frodo is an old IBM Intellistation M which is a workstation server.
It carries the heavy lifting running most of the services (DNS, DHCP,
mail, apache etc.) for the home lan, it's the box which runs my blog,
and a mediawiki site as well as several "intranet" apps. This is
running Ubuntu Dapper, and certainly has Ruby.
Bill is my trusty old slow Thinkpad, only 128MB or ram, kind of slow
and plodding. Ubuntu Feisty including Ruby.
Both of the Ubuntu machines have Ruby installed from source to stay
out of the Debian ruby packaging mess.
Shadowfax is the new addition to the stable, a MacBook which I've
had for just a few days. A nice fast white steed compared to old Bill.
This runs OSX tiger, I'm gradually teaching my old fingers to dance
the Textmate tango instead of the Vim valse.
Arwen is my wifes Compaq something desktop running Windows XP Home
Outside of the Tolkien group theres a Wrt54G running OpenWRT, I
guess this counts as a computer as well.
Lots of other old machines mostly not used, including an old Apple
][+ with Apple Integer Basic rom wrapped up in a plastic bag up in the
attic.