SCSI vs IDE vs FIREWIRE/USB

[Joel Hammer]

I find the 4 drive limitation of IDE machines quite bothersome. Is there
some way, other than scsi, to overcome this limitation in the linux world?

Is setting up a scsi system just a matter of installing a scsi adaptor
and then plugging things in (along with the appropriate drivers)? Is it
worth the extra cost?

Are there easier/better alternatives like firewire/usb peripherals?

Thanks,

Joel