Mouse feet are 100% a necessity, at least so you don't constantly catch on your mousepad.
http://www.razerzone.com/store/razer-mousefeet
direct from razer $10 should be exactly like the original
http://www.hyperglide.net/?hg=paypal-na
$8 if you go directly from their site they do add shipping, for my location it was an extra $1.65 total cost would be $9.60
fyi though shipping is slow as hell
alternatives that I have no idea about the effectiveness of
PTFE mouse tape
http://www.amazon.com/CS-Hyde-PTFE-Mouse-Color/dp/B003DZ16X4
Mouse Feet off ebay $5 would probably be the same as the original
http://www.ebay.com/itm/Tiger-Gaming-Razer-Deathadder-Mouse-Feet-0-65mm-/121071213665
http://www.ebay.com/itm/Tiger-Gaming-Razer-Deathadder-Mouse-Feet-0-65mm-Black-White/141510491088? $3.38