What are some alternatives?
When comparing RadioGet and Serendipity by Spotify, you can also consider the following products
streamripper - Open Source (GPL) application for recording mp3 and ogg music streams
Last.fm - The world's largest online music service. Listen online, find out more about your favourite artists, and get music recommendations, only at Last.fm
SHOUTcast Radio - SHOUTcast Radio is the home of free Internet Radio.
Pandora - Pandora Radio is a free (ad-supported) internet radio founded in 2000.
SoundCloud - Enjoy music & follow favourite artists
Screamer Radio - Screamer Radio is a streaming service that allows users to stream their favorite radio and web casted programming via one easy to use interface.