This may be the best kept secret of the HFU, but we have a wiki. In the past, it's been somewhat difficult to use, as it had a separate account system. Now, it uses the HFU message board account system, so you can log in with your HFU user name and password. The wiki is for creating content for virtually anything radio related. Operators can create a page about their station. Listeners can post QSL card images. There's also articles about various SWBC and utility stations, receivers, software, and assorted technical topics. If it's somehow related to radio, it's welcome on the wiki.
You can access the wiki here:
http://www.hfunderground.com/wiki/Main_PageIf you have not created content on a wiki before, you may wish to read up on media wiki editing:
http://en.wikipedia.org/wiki/Help:Editing and
https://help.wikispaces.com/Editing+a+Page have some basic information.
If you have questions, feel free to ask, either here or on IRC.