What components might I check into that have a small foot print?

I am trying to set up a second system in some cube type shelving that is only 13 inches wide, and 15 inches deep. The hardest thing to accommodate is a CD player. My Fisher tube mono's will fit, and, the Cary SLP 90 preamp will also. Any other suggestions? Also, what if I (god forbid) decided to go solid state so that the system would be user friendly for others. What might I look for? Thank you in advance for any ideas.