Originally Posted by Rumpy
Kenwood (and a few others) makes a "keg" that is pretty much a harddrive for your car. Holds a shit load of songs but it's pretty expensive (I think 500 just for the keg, you need a head unit that will work with it too).
You could get a head unit that plays mp3 encoded discs to cut down on the amount of cd's you need to carry around (can get about 200 songs on an mp3 encoded disc) but it can be a pain in the ass to navigate through all the songs (this is probably the cheapest route). Then there are the new radios that have an input for an ipod and you got the old standby of a cd changer (6-12 discs). I have a 12 disc changer, the head unit I got supports mp3 cd's so I can listen to about 20 discs worth of music at any given time (road trips rule with this shit).
As for the sub, do you want your car to bump? If you like bass, it's the way to go. I got a 600 watt amp and an 8" tube sub (both Bazookas) for about 150. And I fuckin love it. It's exactly what I wanted. Good price and at low volumes it supports and fills out everything nicely and then when you crank it up you can feel it shake your kidneys in the front seat. I throw everything at it, metal, rock, techno, rap and it keeps up like a champ. Only problem is organazing all that shit in your car.
I have a 10 disc Sony cd changer if your interested. Sell it to ya mad cheap (but you need a Sony head unit to use it).