How can I reduce latency while playing World of Warcraft?

I can often have a latency of over 600ms when raiding and I have heard people in-game say that latency can be reduced by using a custom proxy or DNS server (I don't remember which).

Are there any good strategies to reduce latency in WoW, in addition to loading the minimum of addons?

There are a lot of good points brought up on EpicAdvice.com - Tools for lowering latency

lowerping and smoothping both seem to get decent reviews, as well as a blog on elitistjerks that talks about some registry hacks, addon issues, and many other tips for reducing disconnects (which may also help with pings).

I personally use Leatrix Latency Fix. It dropped my latency from ~250ms to ~60ms on all European realms I tried (currently on Draenor).

1) Are you on wireless? If yes, plug it in and get an instant boost.

2) Do you have other things using your connection? My wife and I both play (different computers) and we're at 200 ping. She turns on internet radio, bam we're up to 400 ping. Run a netstat to check for existing connections.