insane: Can you do a Neotrace (free download) to 74.125.15.158? It shows you on a map of the world a graphical representation of your tracert.
When I tracert to that IP using my ISP it goes via Sydney and then to Tokyo and then to Taipei, and then finally to Sunnyvale/San Jose.
When I tracert to what appears to be the youtube cache I use ty-in-f118.google.com it skips the Taipei hop.
Finally download another program called SpeedBit video accelerator, its like a download manager for youtube :)
Hmm, I don't think NeoTrace is using up-to-date geographic info. It claims that 74.125.15.158 goes Auckland -> Perth(!) -> LA -> Sunnyvale, with ty-in-f118.google.com being the same except then going to Tokyo.
However, using services like www.ip2location.com on the IPs, it instead shows it as simply going Auckland -> Hong Kong -> Mountain View (both end here).
One particularly interesting thing this program showed me though is that my gateway is apparently in Auckland...? Even according to that other website. Surely that can't be right... that would mean ALL of my traffic goes via Auckland, but that would explain my latency to it (my gateway)!
I'd rather not resort to something like SpeedBit - I want to treat the illness (or at least identify it), not the symptom.