But down the road ( I mean life after 10.4). I mean G3 is already outdated despite all the hacks going around to install 10.4 onto outdated systems.
Apple has not sold a Mac with a G3 processor for quite some time, it's clear they changed their focus to the G4 processor two and a half years ago. However, Mac OS X 10.4 is supported on all the white "Dual USB" iBooks. No one here knows what the system requirements of the next version of Mac OS X might be.
So G4 will nere really be outdated right?
I'm not sure what you mean by "outdated". Apple will surely continue to support computers with G4 and G5 processors for some time, but they are switching the entire line of Macs over to the Intel processor right now. By the end of the year, Apple won't be selling any computers with G4 or G5 processors...
Keep in mind, the G3 iBook could be almost five years old. If you want to get a wireless card for it, that will cost you well over $100. It has a 10GB hard drive. Mac OS X 10.4 takes up about 3GB all by itself. That won't leave you much room for installing applications or saving many MP3s or photos. And you'll have to buy a copy of Mac OS X 10.4 for $129 to install on it. That iBook comes with NO Mac OS or system install CDs. It says it has 256MB of RAM, and one 128MB chip is soldered in, so you'll have to remove 128MB to add any more and you'll surely want to add at least 512MB if you want to run Mac OS X 10.4. So, you may save a few bucks up front but you'll have to spend another $300-$400 to make sure it's up-to-date, wireless and has enough RAM. If I were you, I'd definitely pay a little more upfront for a newer iBook.
-Doug