Everything fits into the Altoids tin and it easily shuts. Now I have a little radio that's solar charged and has a little LED. That wasn't so bad. It even gets a signal through the Altoids tin.
Plus in a pinch you can swap out the AAA batteries for regular ones OR use the solar cells to charge up other dead NiMh AAA Batteries you have.
Other Ideas that would be easy to do if you're willing to put in the time and parts.
1) Use a rechargeable 3V coin cell or ultra capacitor to save space.
2) Put solar cells on the outside, and speakers inside.
3) Work in some retractable headphones or some speakers.
4) Drill a hole for the LED to stick out the front and also have a button on the outside to work the LED. (if your radio has an LED like mine does. Or heck, wire in your own LED into the circuit.)
Support Me By Buying Some Parts...
If you can't find solar cells or cheap AAA batteries, I have quite a few on my website BrownDogGadgets.com. The same solar cells I use to make my Solar Cockroach would work great for this project. You could also slap on a bigger, more powerful cell onto the outside of the tin.
I also have a wide range fun fun little kits you can put together if you need a little weekend project.