Have you ever played Singstar on the Playstation 2 ? It is a Karaoke like game that is great fun if you play it with some friends. Ultrastar looks clearly like it was inspired by Singstar. The big advantage ? It is completely free and offers many texts for songs on various websites on the internet. You need to download the Ultrastar main program from Sourceforge at the beginning, it is only 500k which means it should be a fast download even for slow connections.