Don't know how easy this would be to set up, or indeed if anyone else would be interested in the idea, but how about a website that not only lists the best challenge sites (like hackergames does) but lets you view your position in each of their rank tables, and then somehow gives you an overall score or rank depending on your progress over all the sites...

comments, suggestions??

the idea is no bad. i also thought about something like that some days ago. it should be something like a challenge network where you can login and then this page can connect to every challenge site to get the information.
it is also no security problem if you can reach the ranking script without beeing logged in. so you don't have to put in your password at this page.(it is not the case at our site but it is easy to change)

then only all user need one username that is always the same.

i really like the idea.

mmmh a challenge network... GOOD!

we could also create only ONE database, hosted somewhere, the challenge sites refer to. So the users don't have to register multiple times...