Interesting.
But i have a few more questions.
< Just a remark, thats one dirty laptop
>
Anyway, i dont really think that using it as heatpipe , by closing both ends with a copper "coin" and filling the interior with some Rxxx, will work properly. The design as it is doesnt really help, because the convection inside it wont be efficient. Hopefully , someone will back me up on this, or correct me (hint hint).
Another thing , isnt it a bit ... small ?
So , real question number one, are you going to use that with a heatpipe system ? And if so, use the tube with that "large" section? And why not try a few copper rods inside (both welded ) to help? Or are you going to use it to transfer heat to a radiator outside the case (or something?) ?
With a solid core , copper, it really depends on the air movement . Having those types of fins, with a regular fan blowing on them, i think only the upper fins will get a decent amout of air through them. The lower ones will probably get a minimum if any.
So, are you going to have one or more lateral fans? A top one? Or a small shroud that covers most of the heatsink and makes the air exit near the base? And how are you going to attach it to the socket?
Zalman already tried something like that in a few of their coolers :
http://www.zalman.co.kr/english/product/cnps5005Cu.htm
http://www.zalman.co.kr/english/product/cnps5100Cu.htm
They do work, but they're not that good.