
I've used this plugin on every single tune I've made.
http://kunz.corrupt.ch/images/products/tal-dub.jpg

Plus Dub delay 2 and 3. They rock, very pleasing sound to them.
I'm a big fan of freeware because I teach music for a living, and freeware provides the perfect platform for people to access computer music for absolutely no cost, and it also provides a consistent platform to teach with, because anyone with a computer can access them, so no system conflicts occur when sharing projects.
I am a massive fan of freeware, so share your favourite plugins/developers, and why you also love freeware

Also, everyone should check this thread
http://www.dubstepforum.com/viewtopic.php?t=54027