I have recently gotten in to Shortwave radio, my aim is to get my amateur licence and get on the air to work the bands myself. At the moment I have two receivers, a realistic DX-200 my main receiver and a Boat anchor valve (tube) receiver for a bit of fun. The antenna is a 10m unbalanced long wire about 4-5 meters up.
I use Linux to do digital signal processing and also display the audio in waterfalls and spectrum displays. Here is a video of a CW session, note the bright spots on the PC that correspond to the CW, in real life I can read the CW from the screen, well I cant as I am still learning but you get the idea :)