A blog that just posts numbers station-like recordings.
A wiki for documenting and discussing radio broadcasts - short, medium, and longwave as well as anomalies, mysteries, oddities, and pirate radio.
The website of an international group of numbers stations enthusiasts. Has a forum, a blog, a podcast (good luck finding the RSS feed), live streams...
This is a site that aims to collect and sort out information about some of the more unusual shortwave anomalies, like UVB-76, the more powerful numbers stations, the XM Whales, and other mysteries. Seems pretty solid, without much in the way of conspiracy, just necessary speculation.
An online noise and sound generator. Has multiple categories and dozens of different sounds, from thunder to to rain to singing bowls, the wind blowing through a canyon, surf sounds, wind sounds in different locales, different voices, and different brainwaves. You can stack up to five of them in a sequence. You can download them, too! Updated periodically, so check back once in a while. The iOS and Android apps are out, too.
Archive of shortwave radio recordings to download.
Just what it sounds like: turn on your shortwave receiver (or drop one of your Conet Project CDs in the player), load up this page, and start crossing off boxes.