Revive your Power MAC (G3,G4,G5) . 


Debian PowerPC 

http://cdimage.debian.org/cdimage/weekly-builds/powerpc/iso-cd/debian-testing-powerpc-lxde-CD-1.iso

Linux Mint Debian 

Instructions: http://www.mintppc.org/content/installation-instructions-mintppc-11

Use this image instead of the "mini.iso" from the link, and then , follow the instructions as usual . http://cdimage.debian.org/cdimage/daily-builds/daily/arch-latest/powerpc/iso-cd/debian-testing-powerpc-netinst.iso

Lubuntu PPC

http://cdimage.ubuntu.com/lubuntu/releases/raring/release/lubuntu-13.04-desktop-powerpc.iso

Burn the ISO file with Toast on MAC or any burning software.
Then. boot any CD on your MAC holding "c" while it boots. Enjoy.

Recommended software for MintPPC or Debian PPC:

Web browser: Iceape. Firefox' cousin, but much faster.
Audio Player: Audacious.
Video Player: Gnome Mplayer.
Image editor: Pinta or Gimp.
Youtube viewer: Minitube.
Mail client: Sylpheed.
PDF viewer: Epdfview.
Office suite: G4 and up: Libreoffice, G3: Abiword, Gnumeric.
IM: Pidgin

Games: 
   No 3D Accel:
Battle for Wesnoth
Prboom
Supertux
Freeciv
Bos Wars
FreeDink
8/16 bit emulators
Flare
    3D: Accel:
OpenArena at low settings
Sauerbraten at lowest settings.
Assault Cube
Eduke32
FreedoidRPG
Lincity-ng
OpenRA (Red Alert) (G4 minimum)

FINALLY, PLEASE DO THIS AFTER INSTALLING MINT PPC, IF NOT; IT WILL
CRAWL TO ITS KNEES DUE A HIGH CPU USAGE:

Open a terminal.  Copy and paste this command:

sudo apt-get remove apt-xapian-index

Press enter.
Type in your root password, and then, reboot.