What do you guys do for a stereo?

I have the stock AM radio in the car and want to keep it there. I would like to play the music from my iPhone in it. I don't care to have CD or FM radio and didn't really want to take up the glove box space with a deck. Here are the options I found:

1) Get a small amp to connect to the player. The only problem is that I read it can be risky if there are any power spikes and I don't want to mess the phone up.

2) This hidden stereo to plug the player into:

http://www.vintagevibes.net/Stereos/secretaudio.htm