First experience was rescuing an old but not so beaten up PowerMac G4 400MHz. It is about to be thrown away on the dumpster.

Cleaned it up, put some hard drive on it, fired it up and it booted on Panther.

Since then, I have bought some things for it;
1. ATI Radeon 9200 PCI Graphics card
2. New Pram battery
3. Another 40GB hard disk
4. Bluetooth dongle
5. Apple Pro keyboard and Mouse
6. Installed Tiger and OS9 on dual boot

Recently, have done a slight overclock to 450MHz.

It is sweet!