If you had to lift a boombox over your head (maybe to do like John Cusack in Say Anything), the Sony RDH-GTK33iP speaker dock should be a good-- if heavy-- choice.
The system is around 90cm wide and 30cm tall and carries a 420W amp feeding x2 stereo speakers (with x2 tweeters and 6" woofers), all inside a heavy duty design. Audio comes through 30-pin iPod/iPhone connector and USB, RCA and line-in ports.
To make things even more impressive (or annoying) each of the twin speakers have colour-changing LED lights pulsating to the music-- with colour schemes including "Forest," "Passion," "Rainbow" or just plain "Random."
Sony has no announcements on availability yet, but the speaker dock should hit the market sometime in 2012.
Go Sony