Ham radio weak signal app WSPR. It's open source and located here:
And tarball located here:
The actual development site is here: http://physics.princeton.edu/pulsar/K1JT/devel.html They don't offer tarballs, only SVN checkouts. Also, it looks like new versions use Qt4.8, so it will have to wait until issue [#4362] is closed.
Package Submissions: #4362