I don't care if it's from the year 2000, it cannot have a hard drive. Not under my roof!
Yeah, that's the way I feel about hard drives now. So I set about figuring out how to get an SSD into the iMac G3. I found this Transcend SSD on Amazon. It is 32GB, so it matches the original capacity of the iMac's 30GB drive well. Most importantly it has a PATA IDE interface, so it should work. I had to purchase a 2.5-inch-to-3.5-inch bay adapter as well as a laptop-to-desktop PATA adapter as well.
(I will write more about the installation later, but it worked great! So now I am running OS9 on a very quite and fast iMac G3)
Here is a somewhat creepy and totally hilarious recent video from Samsung promoting SSDs and why your computer needs one.