[Update: It's gone. The whole thing has been DDOSed out of existence.]
Traceroute is a network tool for figuring out what route a packet takes to get from some point to your machine. This can matter when something is gumming up the works.
If you have a unix machine connected to the internet, odds are you can do traceroute [domain name or IP #] straight from a command line.
If you are on a windows machine you go to a command prompt and type tracert [domain name or IP #] (see the directions here).
For example traceroute google.com tells you about the routing of packets from a big famous internet company.
Play around with it a bit. Once you have the hang of it, on unix try
traceroute -m 200 126.96.36.199
or on windows make it
tracert -h 200 188.8.131.52
(The extra argument tells the trace not to stop after 30 hops, which is is important.)
It should produce something fun. You can also try it from a web-based traceroute interface, but I couldn’t find one that would go over 30 hops, which sort of spoils the fun.
Yes, due to the blizzard in the North East, someone has way too much time on his hands.