Variety of Sound offers free vst plugins on their page. Among them you can find eqs, reverbs, limiters etc. Apart from that, they also have quite an interesting blog.
In case you're wondering why all this is being offered for free, here's a statement by "vos":
As a computer scientist and musician, I’m enjoying designing DSP algorithms and plug-in concepts. It’s a pleasure for me to share my efforts with other people without having to worry about commercial interests. In each of my effects there is a special technical design, workflow or concept combination I haven’t found in existing tools. Many developers these days just stick to old concepts, but you will never see a straight copy of existing gear from me. I always add some innovation, or find a way to evolve and take it to a new level.