Yes, this will work.
You can share a HD by plugging it into the USB port of the Airport Extreme and use the Airport Disk Utility to set it up.
The external drive should have USB2.0 connectivity.
Good Luck
Peter
I have 2 iMacs both the white Intel dual core variety:
#1 is a 24" 250GB HD, 3GB RAM 2.12 GHz (I think) Intel running OS 10.5 (most current updates) the other
#2 is 17" 160GB HD, 1GB RAM, 2 GHz Intel running OS 10.4 (most current updates)
Both of these fine machines are using my airport extreme base station (802.11n (yay!))to connect to the internet. Both of their HD's are nearly full I might have 20 GB between the two. My question is I thought about getting like a 1TB or maybe 2TB external HD and connect it my airport extreme and use it as a network drive to put some of my thousands of songs, photos and movies onto to free up room for more games! Or just put newer stuff on the external (like final cut projects). What are your thoughts and can this be done?

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