anyone know of a good mp3 boombox that can be powered with a cigarette lighter plug in?

No.... But I know some MP3 players that be good to connect to a 12v cigarrette lighter... like the iPod... He, he, he, heeeee

Welcome to the board, kfarm57. Does the box need
to have the ability to play mp3's or will you be
using an ipod or similar to connect to a line-in?
If the latter is the case, there are many boxes with
an external DC power plug which you could use an
adapter to plug into the cigarette lighter.
You get a lot of bang for your buck with the JVC Kaboom.
I think it plays mp3's via the CD player.

brett

yes they have volt converters sold in most major discount or dept stores in the car stereo depts that can power up most appliances thru the cigarette lighter...simply plug your AC cord of your box into the converter then the converter in the cigarette lighter..hope this helps