training websites

[coder1]

Hi, here are some coding websites with problems for training:

www.spoj.pl
www.codeforces.com
www.codechef.com
www.usaco.org


if anyone has more websites, please write them here.

[ne555]

onlinejudge.org
www.programming-challenges.com

Damn, forgot about google code jam.

[vlad from moscow]

It looks like you are the only two who are such trained.:)

[coder1]

@vlad:
how do you train?