Heatpipes are eminently useful for very efficient transfer of heat from the source to another "remote" location where it can be disposed of more easily. The only problem is that the pipe(s) have to be stiff in order to accommodate the wicking structure within, which means you can only produce custom solutions.
said they produced some flexible heatsinks -- but they didn't work as well and cost a fortune. Building a heatpipe at home, I would guess, will be a labour of love and a lot of trial and error. IMO, a water cooled solution with a super quiet pump and passive massive HS (as in power amps) would be much easier to build. The flexibility of the tubes makes it easily adaptable.
Someone is working on an article about a quiet water-cooled PC for SPCR right now.
BTW, almost all the so-called heatpipe-equipped HS are silly gadgets designed only to cash in on a trendy idea. If the pipe is not being used to spread or move the heat to where it could not go otherwise, then it doesn't really serve any purpose. Except for the Shuttle HS systems, the "heatpipe HS" are self-contained affairs no bigger than ordinary HS. They don't make any sense. Some of Thermacore's "even heat" HS devices designed to maximize HS (like a heats preader, but better) make sense, though.