My first juke build used Boston Acoustics 200W 2.1 computer speakers. They rock the house...excellent sound. However, they seem to have gotten out of the computer speaker business. You can still find them around used. If you find a set, I'd highly recommend.
After several people telling me they would be interested in buying that juke, someone finally made a firm offer and is willing to wait until I've completed its replacement. So I am about 75% complete with juke 2.0. In this one, I'm using Some DCM floor speakers I've had sitting around unused. I'm pushing them with a 200W Onkyo receiver. However, if space is a concern, this isn't the setup for you, this thing is a behemoth. Each speaker is a 3 way with a 12" subwoofer. My basement includes a couple of pins and arcade games, so it will fit in.
I looked into the car components, but I really wanted to use these speakers. I'm no electrical engineer and the issues with different impedences scared me away.