If the previous two posts were not enough to get you bored on counters, then here are a few more techniques to implement counters in multi-threaded applications:
Chapter 4 of the book "Why is Parallel programming Hard, and if so, what can we do about it" is devoted solely to counters. The book itself is freely available at the this address (and I recommend it):
They have several implementations, so it is worth the read if you need a fast counter in your multithreaded code.
If that's still not enough, then check out this recent paper on "Scalable Statistics Counters" by David Dice, Yossi Lev, and Mark Moir from Oracle Labs
Pretty cool stuff!