On page 9 of this weeks catalouge 'Seagate 500GB Freeagent Desktop Hard Drive= $179'
I think cheapest on staticICE is $189.
Be aware that the desktop version needs a power outlet and is not powered by USB and in case you didnt know the way Seagate calculates 1GB = 1,073,741,824 bytes. So the advertised 500 GBytes / 1,073,741,824 bytes = 466 Gbytes usable space.
Also unfortunatley no mis-priced Micrsoft items in the catalouge this week :)
Edit: item also avaliable on website and where they also have another 500GB HDD 'Maxtor OneTouch 4 500GB Lite 3.5 External HDD' for $199.
Harvey Norman has a WD 500GB External HDD for $156.